activity Activity emails or emails about Unhandled notifications are never sent

Steps to reproduce

Install NextCloud server
Enable all Activity emails as shown in the screenshot bellow
Wait to receive email notifications without success

Expected behaviour

I wish that my Nextcloud users receive emails about notifications regarding their files. Hence, I've enabled the notifications as shown in the next screenshot. None of them seem to be working however. I don't receive Activity emails as soon as possible and I definitely do not receive Email reminders about unhandled notifications after 1 hour. The only email I think I am actually receiving, is the Daily activity summary and I don't even receive it in the morning,.. The weirdest part is that I receive test emails or other notifications, e.g. password change, but not Activity related ones.

From my research I realize that this is a known issue and it's really frustrating since there are no answers or solutions. No one seems to be caring about this core functionality.

Actual behaviour

Activity emails not working.

Server configuration

Nextcloud version: 26.0.1 PHP version: 8.2 Database: mariadb:10.6

Nextcloud configuration:

<?php
$CONFIG = array (
  'htaccess.RewriteBase' => '/',
  'memcache.local' => '\\OC\\Memcache\\APCu',
  'apps_paths' => 
  array (
    0 => 
    array (
      'path' => '/var/www/html/apps',
      'url' => '/apps',
      'writable' => false,
    ),
    1 => 
    array (
      'path' => '/var/www/html/custom_apps',
      'url' => '/custom_apps',
      'writable' => true,
    ),
  ),
  'memcache.distributed' => '\\OC\\Memcache\\Redis',
  'memcache.locking' => '\\OC\\Memcache\\Redis',
  'redis' => 
  array (
    'host' => 'nextcloud-redis',
    'password' => 'mypass',
    'port' => 6379,
  ),
  'instanceid' => 'ocq4pg6jocqr',
  'passwordsalt' => 'passsalo',
  'secret' => 'secret+n',
  'trusted_domains' => 
  array (
    0 => 'example.com',
  ),
  'datadirectory' => '/var/www/html/data',
  'dbtype' => 'mysql',
  'version' => '26.0.1.1',
  'overwrite.cli.url' => 'http://example.com',
  'dbname' => 'nextcloud',
  'dbhost' => 'db',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'mysql.utf8mb4' => true,
  'dbuser' => 'nextcloud',
  'dbpassword' => 'mypass',
  'installed' => true,
  'app_install_overwrite' => 
  array (
    0 => 'documentserver_community',
  ),
  'mail_from_address' => 'from-address',
  'mail_smtpmode' => 'smtp',
  'mail_sendmailmode' => 'smtp',
  'mail_domain' => 'domain.com',
  'mail_smtphost' => 'server.domain.com',
  'mail_smtpport' => '25',
  'mail_smtptimeout' => '60',
  'enforce_theme' => 'breezedark',
  'skeletondirectory' => '',
  'ldapProviderFactory' => 'OCA\\User_LDAP\\LDAPProviderFactory',
);

Where did you install Nextcloud from: I installed nextcloud via docker-compose. I can provide it if needed.

Under logging, I can see the following Errors each time the cronjob is executed, however I am unsure what they mean or if they are related to my issue.