i cannot enchant two different echanments (armor enchanments)

As far as I know, this is WAI

WAI?

Working as intended. You cannot mix different protection types

basically i cant do anything about it?

Its intentional game design so no, not really. If you really want the enchantments, you could play versions 1.14 - 1.14.2 where a bug allowed the protections to overlap, and then update to a later version if you like.

okay thank you