OB doctor office fraud on Charges??

I changed to the current OB doctor around my 4 months of pregancy since I'd like to deliver my baby in her hospital.

My insurance policy is 100% covered for routine pregnant visit except the 1st visit. I gradually found out almost every regular visit I got charged, so I asked the office department to explain why.

I was told that I got charged several times since they consider the visits as the specialist visit.

For example, during 1 regular visit, the OB doctor asked me how my blood sugar control was going on since I am having blood sugar problem during pregnancy? She always ask the same question every time during the regular visits and I told her sometimes fasting level is higher and then she said better for me to eat more snack like cheese after dinner... The whole conversartion was just around 3 to 5 minutes. I even shared some experience with her how to better control my blood sugar (e.g. lemon water can lower my blood sugar from my personal experience) level since this was my 3rd pregancy...

The doctor office manager insists that this kind of conversation should not belong to the topic of routine visit, so it should be considered as specialist and charged. Actually one month ago the OB doctor had already referred me to see the diabetes specialist to control my blood sugar issue and I had paid that visit already.

I tried to talk to the doctor to get her support but she said that she knows nothing about insurance...

Do you have the similar situation before that you come to the regular visit/checkup, but then they charge you for the extra as the specialist visit. It was the OB doctor who asked me the question first, and I do not understand why I was charged just because of it.

Do you know who I can ask for help?