Patch on head

I know its a bit blurry I'll try to get a better one

If it looks kinda like a scab/crease/crack on the head give the snake a good soak and check your humidity levels.

Was it possibly noticed right after his last shed? One of mine shed and a head scale came with the shed and left a raw spot (it was one of the snakes I rehabbed and sold to HadesBP on here.) In another few sheds he was back to normal.