Your requirements could not be resolved to an installable set of packages.

[pishguy]

  Problem 1
    - pragmarx/tracker v4.0.x-dev requires laravel/framework ^5.5 -> found laravel/framework[v5.5.0, ..., 5.8.x-dev] 
    - but it conflicts with your root composer.json require (^8.12.1).
    - pragmarx/tracker[v4.0.0, ..., v4.0.1] require doctrine/dbal ^2.6 -> found doctrine/dbal[v2.6.0, ..., 2.12.x-dev] 
    - but the package is fixed to 3.0.0 (lock file version) by a partial update and that version does not match. 
    - Make sure you list it as an argument for the update command.
    - Root composer.json requires pragmarx/tracker ^4.0 -> satisfiable by pragmarx/tracker[v4.0.0, v4.0.1, v4.0.x-dev].

Use the option --with-all-dependencies (-W) to allow upgrades, 
downgrades and removals for packages currently locked to specific versions.

[mintalicious]

There is also this issue: https://github.com/antonioribeiro/tracker/issues/536

[moacdev]

Look at https://github.com/antonioribeiro/tracker/issues/536