Board Thread:Shadow Fight 2 Discussion/@comment-188.147.37.83-20190822200618/@comment-31479589-20190823033622

Afaik, beating every single boss is not a requirement for getting the helms. It's only necessary in the sense that they drop key which is required to fight the next boss, all the way up to Tenebris' key.

You said that your raid progress is restored, right? This is my best guess on what might've happened: the game thinks you already obtain the helm, thanks to your raid progress being saved. Your new progress doesn't have the helms, but the restored raid data thinks you already have them, which led to this error being registered.

This is just a guess and might not be true, but this is lame nonetheless. You should try to contact Nekki Support and complaint to them, hopefully they listen.