My hair does the same thing. The only solutions I've found:
-Twist or braid it at night. Untwist/braid and fluff
-CW hair in the AM
-Dampen hair with a moisture spritz, and then use wet fingers and a product like Curls Milkshake or Blended Beauty Styling Butter Creme (or another of their styling products) to scrunch and fuff. Those days I ususually use a scarf or other hair accessory.