I might have found a possible solution to this a while ago, but when I lost my Thanos model I equipped a title onto it. It wasn't in my inventory but I could still add titles/effects to it. Try to add a title to it, it fixed my problem

I might have found a possible solution to this a while ago, but when I lost my Thanos model I equipped a title onto it. It wasn't in my inventory but I could still add titles/effects to it. Try to add a title to it, it fixed my problem