Mustela foam shampoo was amazing for us. Gone in a couple of days.
I second @Charlotte
Yes rubbing in coconut oil 15 mins before bath worked for both my babies too. Then gently combing off the flakes whilst washing with dentinox cradle cap shampoo. Gone in a week.
Coconut oil on for 15 mins before a bath then use a silicon brush to get off in the bath
Olive oil is really good and worked wonders on my little boy x
Gp said just use the cheapest baby oil because they have the least ingredients