Username validation using Regis on Laravel

Please find the validation script below to fix the username validation allowing it to have only Alphanumeric with dot (.), dash/hypen (-) and underscore(_).

$validator = Validator::make($request->all(),
            ['user_name' =>
                ['required', 'min:4', 'max:20', 'unique:auth_users', 'Regex:/^[a-zA-Z0-9-._]+$/']
            ]