using different model for user authentication

I want to use a different model (Member) for user authentication throughout my entire laravel application.

So the first logic step would be to make the member model authenticable:

// Member.php

use Illuminate\Foundation\Auth\User as Authenticatable;

class Member extends Authenticatable
{

    protected $table = 'members';
    protected $fillable = [
         'first_name', 'last_name', 'email', 'password'
    ];
    protected $hidden = [
        'password', 'remember_token',
    ];

}

then in auth.php:

    'defaults' => [
        'guard' => 'member',
        'passwords' => 'users',
    ],
    'guards' => [
        'web' => [
            'driver' => 'session',
            'provider' => 'users',
        ],
        'member' => [
            'driver' => 'session',
            'provider' => 'members',
        ],
    'providers' => [
        'users' => [
            'driver' => 'eloquent',
            'model' => App\Models\User::class,
        ],
        'members' => [
            'driver' => 'eloquent',
            'model' => App\Models\Member::class,
        ],

if i then create a user in tinker, the user gets created

but attempting to fill in the form at/login, i get an error: these credentials do not match our records

i came across this:

https://laravel.com/docs/5.6/authentication#adding-custom-guards

if i understand it correctly, i still use the session guard, so i don't need a custom guard?

Can someone tell me what i am missing? Why i can't login? If any further information is required, please let me know, i will gladly add it.