LDAP Configuration Laravel5 - Authentication user provider [adldap] is not defined

I'm fresh beginner in Laravel 5.8 and i'm trying to develop an app with LDAP authentication.

I use this package : https://adldap2.github.io/Adldap2-Laravel/#/auth/setup

And i got this error : Authentication user provider [adldap] is not defined. Does anyone know this error and could tell me where my configuration can be wrong ?

Thansk for your help :)

via Chebli Mohamed