Greasy hair stain on non-removable headboard

[filka]

My bed has a button-back headboard with a shiny synthetic material. I have naturally greasy hair so when I sit up in bed it leaves a mark which is gradually getting worse. OH has dry hair so the other side is OK.

How can I clean this?

Hmmm. Can’t tell your material but I had a silky one and isopropyl alcohol, dabbing and letting it dry did the trick. Try in a corner or see what the manufacturers say? Mine were not helpful.
Also, I invested in cushions. It’s easier to bin the cushion cover than the bed.

A stain remover spray might get rid of it.

I'd try upholstery shampoo.

Baby wipes.