Compostable file keeps rewriting itself even when locked.

I added some custom items i want to be compostable, however I can't make them since every time I add them to the list in the game files with probability to other compostable items its just getting deleted. I tried locking item extensions I made for items i made in MCreator but it's still deleting the custom made items in that list. I can't add the item the usual way since MCreator doesn't see custom items. So I'm confused what I should do to make my custom items be compostable if MCreator keeps deelting them even after locking from the list in files.