Objects disappearing from crypto-matte

I have an issue with my cryptomatte. Objects, in this case the mountains and the center flying product, pop out of the cryptomatte and don’t know what’s going on. Can someone help please? Thanks

Ok, I found what was going on:

For some reason I´m not using Nanite meshes (don´t ask me why, something related to the grass) but specifically the objects popping out of their mattes (2 mountains and a flying product) had Nanite enabled. I assume then that this was a distance issue (mountains getting to far and product to close).

Anyway, I disabled the Nanite mesh option and cryptos worked fine