6 month diet--expected wt. loss??

Can anyone tell me if there is a minimum or expected amount of weight loss you are suppose to have for the 6 month physician supervised diet for insurance approval?? I've completed the 6 months and only lost 12 lbs. so now I'm worried that I'll be denied because of some insurance expectation. I have Cigna insurance and I've heard good and bad about them. My initial consult is next week so you know---I'm coming up with all kinds of "what ifs". I'd appreciate any input--thanks!!