Not recognized more than one rule

Select::make('frequency')
                ->options([
                    'weekly' => 'Semanalmente',
                    'fortnightly' => 'Quincenal',
                    'monthly_twice' => 'Dos veces al mes',
                    'monthly' => 'Mensual',
                    'quarterly' => 'Trimestral',
                    'annually' => 'Anualmente',
                ])->required(),
                TextInput::make('frequency_day_1')->numeric()->rules([function (Closure $get) {
                    $frequency = $get('frequency');
                    \Log::alert($frequency);
                    switch ($frequency)
                    {
                        case 'weekly':
                            return 'max:7|min:1';
                            break;
                        case 'fortnightly':
                            return 'max:7';
                            break;
                        default:
                            return;
                            break;
                    }
                }]),