Filament\Forms\Components\Select::isOptionDisabled(): Argument #2 ($label) must be of type string,

I get this error on a select filter with relationship

Filament\Forms\Components\Select::isOptionDisabled(): Argument #2 ($label) must be of type string, App\Enums\ProductType given,

SelectFilter::make('product_type')->label('Product Type')->relationship('product', 'product_type')->options(ProductType::class),

Any possible solution on this....