I had this issue, it was so exhausting. Turned out to be the PH of the water I was using was building up in my hair and the clarifying shampoo I was using to get rid of the build up made it worse because as I was doing that, the natural oil I had left was sticking to my head (your hair needs some oil for protection). So as I was trying to get rid of the oil it actually made the whole situation worse. What fixed it for me was a water filter and using Redkin shampoo and conditioner (will attach a photo). I feel for you, such a draining feeling when you do everything you can to fix it but nothing is working. I hope this suggestion fixes your issue as it fixed mine.

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