Some enchanting mods with shield enchantments are incompatible with the Atum shields (Atem's protection, etc). It seems as if other mods do not find the Atum shields as a "shield item" in the first place. I've tried to apply the enchantments using the enchantment table, anvil, and even commands. Even when using commands, I get a message the Atum shields "cannot support that enchantment". This leaves me to believe that the game does not find the Atum shields as a "shield". It may be a different issue perhaps but I'm not sure.
This issue is not an issue with other modded shield items. For example, there are enchantments for shields that can be applied on say Twilight Forest shields, but they cannot be applied to any of Atum's shields. I'm curious why this happens and would be grateful if the issue can get fixed.

The Mods I used were: Atum 2 (latest), Twilight Forest (latest), and Wonderful Enchantments Mod (latest) on 1.16.5

I can provide files if needed, but I'm not sure if they will provide any answers atm.
Thank you for the help!

According the discord people, it might be an issue regarding "shielditem (?)". A person told me that: "Also, looks like the Shield in Atum doesn't extend ShieldItem, which is why it doesn't find it." Thought this might help out... I have no coding knowledge whatsoever, so I don't really know.