Error in composer update after removing a package.

I have updated laravel version from 5.4 to 5.5. Then I have removed a package from composer.json. While I run a command in terminal "composer update" I am getting a error.

[email protected]:~/Code/cabinapi$ composer update

Loading composer repositories with package information

Updating dependencies (including require-dev)

Nothing to install or update

Generating optimized autoload files

Illuminate\Foundation\ComposerScripts::postAutoloadDump

@php artisan package:discover

In ProviderRepository.php line 208:

Class 'Jenssegers\Mongodb\Session\SessionServiceProvider' not found

**Script @php artisan package:discover handling the post-autoload-dump event returned with error code 1**

Most of the time that I have this error is because I forgot to remove it from the config.

Do you have the Jenssegers\Mongodb\Session\SessionServiceProvider in your config/app.php? And doesn't it exist anymore? If you have remove that package, you can remove the config line.