Ice & Fire Mod armor gone?

In a minecraft world I activated ice & fire with a few other mods (biome, mining) keep inventory. However, my Dragon Scale armor (it was enchanted, I had it on) was gone after I died.

The reason for the kill was that I (don't remember what it's called) transformed / enchanted me into something… Could it be because of that?

I've never heard of anything like that, but there were probably some complications because these are mod items

I have already noticed that the Ice & Fire armor like to disappear after death, whether with keepInventory or gravestones. It's just a bug.