I've recently set up a new `Laravel 5.5` project on `Ubuntu 16.04` with an `NGINX` server. I've followed all the correct steps and double checked everything more than once. I've installed `Laravel/Passport` and double checked those set up instructions as well.

I'm building an `API` that requires a login for most endpoints, which is done via `password_grant` with `laravel/passport` but can also consumes a `Facebook` auth token - instead of writing my own Facebook Auth Token verify, I've chosen to use a larval plugin. [`composer require danjdewhurst/laravel-passport-facebook-login`](https://github.com/danjdewhurst/Laravel-Passport-Facebook-Login) However, this plugin doesn't seem to install easily for me.

I am receiving an error on any `composer` install or update command I issue:

> 
> Target [League\OAuth2\Server\Repositories\ClientRepositoryInterface] is not instantiable while building [League\OAuth2\Server\AuthorizationServer].
> 
> 
> 

I have played around with the `config/app.php` file as well as the `uses` for all of the files and providers that were installed with the plugin. I have gone through every post here to try and fix the issue as well.

If anyone has any insight or a fix for this issue I'd appreciate it. Any help would help.

Thank you.