NOP 4.4 Product attribute not working...

Hi! i have strange situation, and don't know what to do with it.

We use Product attribute "gift wrapping". Product attribute is associated with product "gift wrapping" (dont manage stock). In Nop 4.1 it's worked fine, but after we moved to 4.4 we have problem...

The same products / same settings / and some products have possibility to use gift wrapping... but the others has unclickable "gift wrapping option"

We can open dropdownlist and can't choose anything.

Is the same product / same settings / all the same and in 4.1 version it's works ok... any idea why in 4.4 it's stop working? Maybe you have similar issue? or it's bug in nop 4.4?

Would you show us some screen shots?

Hi! i don't have but just found solution.

I change set Display type for attribute value when out of stock to "always display". And now i don't understand why this make change... Maybe main "grouped product" have 0 stock?

Or maybe any idea why this impact to block attributes?