Daughters hair

I’m needing some help with what shampoo or products to put in my daughters hair. She is part Native American part Hispanic and part white. The top of her head is flat as can be but the back is textured and gets matted so easily. I brush her hair multiple times a day and am currently using J&J curly shampoo and conditioner but they aren’t helping her hair. I have super straight hair with no texture so I don’t know what to use to help her hair. Please help