Shampoo/conditioner recommendations for thinning fine hair and daily use?

I have straight, fine hair and wash it everyday (I have to or else it gets greasy and dull). In the last year, I’ve developed a cowlick in the back which is changing my part and showing small balding spots. My hair has never been this thin before and I don’t know what to do.

For reference I’m 29 and used to get it professionally colored but stopped so my natural hair can come through.

I used to use Biolage and then switched to Pureology. Now I use a Pureology (purple shampoo) twice a week and the Monday shampoo/conditioner for the remainder of the week which I don’t love.

Any tips would be greatly appreciated!