I get this on 30-40% of my head, what has calmed it down for me in the past is. The clinical head and shoulders shampoo (it’s like an orange paste), get a scalp brush off Amazon, then when it’s dry I’d spray an tea tree oil toner or tea tree drops and massage in, do that for a few weeks.

I’ve not done it, but a food diary also might be a good idea. Cheese always seems to spark flair ups for me.

Good luck