mutateFormDataBeforeCreate not working

class RoomResource extends Resource
{
    protected static ?string $model = Room::class;

    protected static ?string $navigationIcon = 'heroicon-o-rectangle-stack';

    protected static ?string $navigationGroup = 'Room Management';
    
    public static function form(Form $form): Form
    {
        return $form
            ->schema([
                Select::make('room_type_id')
                    ->required()
                    ->label('Tipe Kamar (ID)')
                    ->options(Room_type::pluck('name_room_id', 'id')->toArray()),
                TextInput::make('count')
                    ->label('Jumlah Kamar')
                    ->type('number')
                    ->minValue(1)
                    ->required()
                    ->dehydrated(false)
            ]);
    }

    protected function mutateFormDataBeforeCreate(array $data): array
    {
        dd($data);
        if (!isset($data['count']) || !is_numeric($data['count']) || $data['count'] <= 0) {
            throw new \InvalidArgumentException('Jumlah kamar harus lebih dari 0.');
        }
        $count = (int) $data['count'];
        $rooms = [];
        for ($i = 0; $i < $count; $i++) {
            $rooms[] = [
                'room_type_id' => $data['room_type_id'],
                'status' => 'Available',
                'tenant' => null,
                'created_at' => now(),
                'updated_at' => now(),
            ];
        }
        Room::insert($rooms);
        return [];
    }