Class 'Symfony\Bundle\MonologBundle\MonologBundle' not found

[WafieAli]

Hi all,

Recently I have done mass upgrade on cpanel for php and mysql and it cause a lot of disasters after(not sure if due to codes itself since this is handovered from existing project). When to access one of the domains it returns 500 error. The one of the errors shown is as per below:-

[02-Sep-2021 14:57:36 Asia/Kuala_Lumpur] PHP Fatal error:  Uncaught Error: Class 'Symfony\Bundle\MonologBundle\MonologBundle' not found in /home/mpn2u/public_html/p3/yinson/app/AppKernel.php:20
Stack trace:
#0 /home/mpn2u/public_html/p3/yinson/app/bootstrap.php.cache(2581): AppKernel->registerBundles()
#1 /home/mpn2u/public_html/p3/yinson/app/bootstrap.php.cache(2410): Symfony\Component\HttpKernel\Kernel->initializeBundles()
#2 /home/mpn2u/public_html/p3/yinson/app/bootstrap.php.cache(2442): Symfony\Component\HttpKernel\Kernel->boot()
#3 /home/mpn2u/public_html/p3/yinson/public/app.php(29): Symfony\Component\HttpKernel\Kernel->handle(Object(Symfony\Component\HttpFoundation\Request))
#4 {main}
  thrown in /home/mpn2u/public_html/p3/yinson/app/AppKernel.php on line 20

Upon searching from previous similar issues on class not found, I run composer require symfony/monolog-bundle and it return this error log:-

composer require symfony/monolog-bundle
Using version ^3.7 for symfony/monolog-bundle
./composer.json has been updated
Running composer update symfony/monolog-bundle
Loading composer repositories with package information
Updating dependencies
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - symfony/http-kernel[v4.4.0, ..., v4.4.30] require symfony/error-handler ^4.4 -> found symfony/error-handler[v4.4.0, ..., v4.4.30] but it conflicts with your root composer.json require (^5.3).
    - libre-informatique/crm-bundle is locked to version 0.6.4 and an update of this package was not requested.
    - Conclusion: don't install symfony/http-kernel v5.1.2 (conflict analysis result)
    - Conclusion: don't install symfony/validator v3.4.32 (conflict analysis result)
    - Conclusion: don't install symfony/validator[v3.4.34] | install one of symfony/http-kernel[v5.1.4, ..., v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/validator[v3.4.33] | install one of symfony/http-kernel[v5.1.3, ..., v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.1.5 (conflict analysis result)
    - Conclusion: don't install symfony/validator v3.4.35 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.1.6 (conflict analysis result)
    - Conclusion: don't install symfony/validator v3.4.36 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v5.1.4] | install one of symfony/http-kernel[v4.1.12, ..., v4.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v5.1.3] | install one of symfony/http-kernel[v4.1.11, ..., v4.2.10] (conflict analysis result)
    - symfony/http-kernel[v4.1.11, ..., v4.1.13] require symfony/event-dispatcher ~4.1 -> satisfiable by symfony/event-dispatcher[v4.1.0, ..., v4.4.30].
    - Conclusion: don't install symfony/event-dispatcher v4.1.0 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v4.2.0] | install one of symfony/http-kernel[v5.1.7, ..., v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/validator[v3.4.37] | install one of symfony/http-kernel[v5.1.7, ..., v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v5.1.7] | install one of symfony/http-kernel[v4.2.1, ..., v4.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v4.2.1] | install one of symfony/http-kernel[v5.1.8, ..., v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/validator[v3.4.38] | install one of symfony/http-kernel[v5.1.8, ..., v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.1.9 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.1.1 (conflict analysis result)
    - Conclusion: don't install symfony/validator v3.4.39 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v5.1.8] | install one of symfony/http-kernel[v4.2.2, ..., v4.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v4.2.2 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.1.2 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.1.10 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.1.3 (conflict analysis result)
    - Conclusion: don't install symfony/validator v3.4.40 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v4.2.3 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.1.4 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v4.2.4] | install one of symfony/http-kernel[v5.1.11, ..., v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/validator[v3.4.41] | install one of symfony/http-kernel[v5.1.11, ..., v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v5.1.11] | install one of symfony/http-kernel[v4.2.5, ..., v4.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v4.2.5] | install one of symfony/http-kernel[v5.2.0, ..., v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/validator[v3.4.42] | install one of symfony/http-kernel[v5.2.0, ..., v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.2.1 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.1.5 (conflict analysis result)
    - Conclusion: don't install symfony/validator v3.4.43 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v5.2.0] | install one of symfony/http-kernel[v4.2.6, ..., v4.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v4.2.6 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.1.6 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.2.2 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.1.7 (conflict analysis result)
    - Conclusion: don't install symfony/validator v3.4.44 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v4.2.7 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.1.8 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v4.2.8] | install one of symfony/http-kernel[v5.2.3, v5.2.4, v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/validator[v3.4.45] | install one of symfony/http-kernel[v5.2.3, v5.2.4, v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v5.2.3] | install one of symfony/http-kernel[v4.2.9, v4.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/validator[v3.4.46] | install one of symfony/http-kernel[v5.2.4, v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v4.2.9] | install one of symfony/http-kernel[v5.2.4, v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v5.2.4] | install symfony/http-kernel[v4.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel[v4.2.10] | install symfony/http-kernel[v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/validator[v3.4.47] | install symfony/http-kernel[v5.2.5] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.2.5 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.1.9 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.1.10 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.1.11 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.1.12 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.2.0 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.2.1 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.2.2 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.2.3 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.2.4 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.2.5 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.2.6 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.2.7 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.2.8 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.2.9 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.2.0 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.2.10 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.2.1 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.2.11 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.2.2 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.2.12 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.2.3 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.3.0 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.0 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.2.4 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.3.1 (conflict analysis result)
    - Conclusion: don't install symfony/validator[v4.2.5] | install one of symfony/http-kernel[v5.2.6, ..., v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.2.6 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.3.2 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.1 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.2.6 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.3.3 (conflict analysis result)
    - Conclusion: don't install symfony/validator[v4.2.7] | install one of symfony/http-kernel[v5.2.7, v5.2.8, v5.2.9, v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.2.7 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.3.4 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.2 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.2.8 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.3.5 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.2.8 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.3.6 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.3 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.2.9 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.3.7 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.2.9 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.3.8 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.4 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.2.10 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.3.9 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.4.12] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.4.11] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.4.10] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.4.9] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.4.8] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.4.7] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.4.6] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.4.5] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.4.4] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.4.3] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.4.2] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.4.1] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.4.0] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.3.11] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher[v4.3.10] | install symfony/http-kernel[v5.2.10] (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.2.10 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.4.13 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.5 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.2.11 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.4.14 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.4.15 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.2.12 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.4.16 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.3.0 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.4.17 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.3.1 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.4.18 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.3.2 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.4.19 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.3.3 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.4.20 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.3.4 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.4.25 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.3.5 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.4.27 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.3.6 (conflict analysis result)
    - Conclusion: don't install symfony/event-dispatcher v4.4.30 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.3.7 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.6 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.3.8 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.3.9 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.7 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.8 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.9 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.3.10 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.3.11 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.10 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.2.11 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.11 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.12 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.2.12 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.13 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.14 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.2.13 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.15 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.16 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.2.14 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.17 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.18 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.3.0 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.19 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.20 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.3.1 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.21 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.22 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.3.2 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.24 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.25 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.3.3 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.3.4 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.3.5 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.3.6 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.26 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.27 (conflict analysis result)
    - Conclusion: don't install symfony/http-kernel v5.3.7 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.29 (conflict analysis result)
    - Conclusion: don't install symfony/validator v4.4.30 (conflict analysis result)
    - sonata-project/doctrine-orm-admin-bundle 3.13.0 requires sonata-project/admin-bundle ^3.29 -> satisfiable by sonata-project/admin-bundle[3.57.0].
    - blast-project/utils-bundle 0.6.4 requires sonata-project/doctrine-orm-admin-bundle >=3.1 -> satisfiable by sonata-project/doctrine-orm-admin-bundle[3.13.0].
    - libre-informatique/crm-bundle 0.6.4 requires blast-project/utils-bundle 0.6.4 -> satisfiable by blast-project/utils-bundle[0.6.4].
    - Root composer.json requires symfony/monolog-bundle ^3.7 -> satisfiable by symfony/monolog-bundle[v3.7.0].
    - symfony/monolog-bundle v3.7.0 requires symfony/http-kernel ~4.4 || ^5.0 -> satisfiable by symfony/http-kernel[v4.4.0, ..., v4.4.30, v5.0.0, ..., v5.3.7].
    - symfony/http-kernel v5.1.1 conflicts with symfony/http-kernel v5.1.1.
    - symfony/http-kernel v5.1.0 conflicts with symfony/http-kernel v5.1.0.
    - symfony/http-kernel v5.0.11 conflicts with symfony/http-kernel v5.0.11.
    - symfony/http-kernel v5.0.10 conflicts with symfony/http-kernel v5.0.10.
    - symfony/http-kernel v5.0.9 conflicts with symfony/http-kernel v5.0.9.
    - symfony/http-kernel v5.0.8 conflicts with symfony/http-kernel v5.0.8.
    - symfony/http-kernel v5.0.7 conflicts with symfony/http-kernel v5.0.7.
    - symfony/http-kernel v5.0.6 conflicts with symfony/http-kernel v5.0.6.
    - symfony/http-kernel v5.0.5 conflicts with symfony/http-kernel v5.0.5.
    - symfony/http-kernel v5.0.4 conflicts with symfony/http-kernel v5.0.4.
    - symfony/http-kernel v5.0.3 conflicts with symfony/http-kernel v5.0.3.
    - symfony/http-kernel v5.0.2 conflicts with symfony/http-kernel v5.0.2.
    - symfony/http-kernel v5.0.1 conflicts with symfony/http-kernel v5.0.1.
    - symfony/http-kernel v5.0.0 conflicts with symfony/http-kernel v5.0.0.
    - sonata-project/admin-bundle 3.57.0 requires symfony/validator ^3.4.30 || ^4.2 -> satisfiable by symfony/validator[v3.4.30, ..., v3.4.47, v4.2.0, ..., v4.4.30].
    - Conclusion: don't install symfony/validator v3.4.31 (conflict analysis result)


Installation failed, reverting ./composer.json and ./composer.lock to their original content.

I have refers to several questions on this matter including on github but seems no way out for me. I am full of hope to seek advice on which matter I might mislooked. This issues will cost us a lot in terms of compensations from clients. Thank you.