Kitara and Lee JB are right, as usual.
You will have to lose weight all over, and it will seem that you are not losing any in the hip and thigh area, because that is where you have the most fat stored. It just takes time, if the hips and thighs are the first place you started noticing weight gain, then it will be the last place you will see it leave.
Stick with it.
Diet
Cardio
Weights