Laravel composer is different at PROD

Question

My app is running ok at DEV but in production, the command composer update is running on an error as follows:

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

Problem 1
    - mpdf/mpdf[v7.1.0, ..., v7.1.6] require php ^5.6 || ~7.0.0 || ~7.1.0 || ~7.2.0 -> your php version (7.4.28) does not satisfy that requirement.
    - mpdf/mpdf[v7.1.7, ..., v7.1.9] require php ^5.6 || ~7.0.0 || ~7.1.0 || ~7.2.0 || ~7.3.0 -> your php version (7.4.28) does not satisfy that requirement.
    - Root composer.json requires mpdf/mpdf ^7.1 -> satisfiable by mpdf/mpdf[v7.1.0, ..., v7.1.9].

So I run the command sudo composer require mpdf/mpdf and the result is another error:

Problem 1
- Root composer.json requires pusher/pusher-php-server ~3.0, found pusher/pusher-php-server[3.0.0, ..., v3.4.1] but the package is fixed to v4.1.5 (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.
Problem 2
- Root composer.json requires santigarcor/laratrust 5.0.*, found santigarcor/laratrust[5.0.0, ..., 5.0.x-dev] but the package is fixed to 4.0.5 (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

Well, I did update the Laratrust to version 5, but didn't do anything at pusher… So why is that error?

Any ideas? Thanks!