Head armour bug.

Hello!

I have a little bug: In my MCPE world, I created a map. In that map, wearable pumpkins are very important, but I can't put a pumpkin or any helmet on my head. I can still wear the rest of the armour. And the weird thing is: this bug is only at one of my worlds. Could you please fix this?

Maybe important: I tried restarting my phone and I have the latest version of MCPE (2020 19 April).