*UPDATE* Flakey Dandruff Fix

I have the worst dandruff. It is huge flakes of Dandruff on my scalp that are hard to get out of my hair like in the pic below. I have tried several shampoo and oil treatments and nothing has worked. I could wash my hair and the next day it’ll be back to Dandruff. Not sure if this matters but I am African American and have no idea how to treat this? Please help.

*UPDATE* saw a dermatologist have dermatitis. I bought the nutrogena Tgel 2-1 shampoo and conditioner. Works wonders! Smells great and most importantly my flakes and dandruff are gone!!!!!! Thank you ladies.