Licensed cosmetologist here: dandruff is oily and is hard to get out of hair, dry skin flakes out easily. I suffer from eczema all over my scalp- I FEEL YOU. People ALWAYS confuse dandruff and dry skin. I didn’t even know the difference until I went to school. Best bet is see a dermatologist as I am sadly not a doctor. But I can atleast try to make it manageable for you. Should possibly try shampooing about twice a week. It takes time but in about a month-month and a half your hair should be slightly less oily and more manageable. Make sure your staying hydrated with water and make sure your eating healthy and getting the nutrients you need. Oily fish (like salmon) contain omega-3 fatty acids. Which stimulate the sebum glands. Vitamin A (carrots, pumpkin, any orange root veggies) are good for sebum production. Note: if you take this advice you will need to monitor your scalp weekly and ease off these foods once natural balance is restored. Could be product build up- once or twice a month use a clarifying shampoo to really get a deep clean. Even if you don’t use any product to style it could be extra bits of shampoo not rinsing out. Try shampoo for sensitive skin and without sulphate. Honestly I’m a fan of fantastic sams brand shampoos. They aren’t as expensive as the more name brand products but it’s better than Pantene and seldom blue. That stuff leaves a film of oil over your hair strands so it appears shinier and healthier. Get a moisturizing hair mask for your hair and scalp. Should be available at any salon. A pricier option is to also see if any salons around you sell nioxin and see if they can get you some of the extra strength scalp recovery. Regular strength is for dandruff and extra strength is for dry scalp. Hope I helped!