Fix EXTREMELY dry hair/scalp?

so I have good hygiene and I wash my hair every other or every two days as directed by my hairdresser, I condition it, I never straighten it, I let it air dry. But there’s this one spot on my scalp that’s so dry if I scratch it this happens..then I get obsessed with scratching and making all

The flakes go away and I’m sure that doesn’t help.

Idk what to do! I’ve tried deep conditioning, I’ve tried Head and shoulders, I’ve tried it all. Please help.