Get users emails with role admin in spatie/laravel-permission

Hi I'm using laravel spatie for manage user roles and permissions. What I need is to get a list of user emails with a specific role. Here is my code.

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use App\Models\User;
use Spatie\Permission\Models\Role;
use Auth;

class StripeController extends Controller {

    public function subscribe(Request $request) {
        $users = User::select('email')->get();
        var_dump($users->pluck('email'));
        exit();
    }
}

In this code I get mails of all users. But I need only users have the role admin. It would be great if someone can help. I'm using this package to get roles.

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