Laravel - Class 'Illuminate\Pagination\PaginationServiceProvider' not found

On my website I am getting this error

Class 'Illuminate\Pagination\PaginationServiceProvider' not found

I've searched everywhere and they tell me to composer install and add that package to my composer.json file

Whenever I do Composer install or Composer update I am presented with this:

 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
 You made a reference to a non-existent script @/usr/local/bin/php artisan package:discover

This is a fairly fresh install of laravel.

This is my composer.json file: https://pastebin.com/0dMuKtM5

And this is my config/app.php https://pastebin.com/HyxjkB1j

In reference you can see my website here: http://staging.creativehedgehog.co.uk/

via Chebli Mohamed