I feel that its due to the change in Season that has caused you to see more of a dullness return to your hair. Winter weather can wreak havoc on hair if it is not being properly hydrated. I would suggest you washing your hair with a mild cleanser, following it up with a hydrating and detangling conditioner, using a moisturizing styling product that will not only help with frizz control and definition but will leave your curls looking more manageable.

Remember your hair needs hydration and not weight to it because of the hairtype that you possess.

Here's what I would recommend for you to give a try from CurlMart:

Curl Junkie Chamomile and Jasmine Conditioning Shampoo
Curl Junkie Give 'em The Slip! Instant Conditioner
Curl Junkie Hibiscus and Banana Honey Creme Leave-In Conditioner/Fine
Curl Junkie Intense Protection Leave-In Conditioner-Fine

And if you desire more hold to your hair you can always apply styling gel over either of the Curl Junkie leave-ins to finish off your style with. These products are all designed to be compatible with curly hair that is of the Type 2 variety.
"Curls Tester"
Products in my current regime: Nioxin Scalp Therapy Shampoo, ORS Replenishing Pak, Curls Whipped Cream, Curls Souffle, Curls Spiral Curls Cream, Curls Milkshake, Curls Quenched, BB(Bonner Brothers) Growth Lotion