Composer update issues

I ran php composer.phar update using ssh on my shared hosting, it installed/updated the dependencies and upgraded my laravel 5.1 to 5.7 but then i got these fatal errors when i opened my site that was previously returning 404 error on all pages except the homepage, now it's saying it can't find some files

Class 'Illuminate\Routing\ControllerServiceProvider' not found [Symfony\Component\Debug\Exception\FatalThrowableError]

Now even the homepage is not working anymore.

Note: i followed instructions from previous question here and removed the entries from config/app but that did not fix it.

via Chebli Mohamed