Gentle Dental trying to collect what my insurance will not pay them from me and is keeping double payments. I overpaid ins. allowable amount too, they won't return phone calls. Boca Raton, Florida

On my first dental visit I was told of the cost, 1/2 to me and 1/2 to my insurance carrier GEHA. I was required to pay $1995 before leaving.  GEHA allowable payment was $1589.50. Gentle Dental wants me to pay the difference of what my insurance co. is not allowing - $355.50.  I went to the dental group because they are on my GEHA plan and also on my BCBS plan.  They only bill for one ins. and I bill for BC/BS which is very limited. I have paid what was expected from BC/BS as requested and now Gentle Dental is double paid with these payments.  Gentle Dental is not following GEHA allowable charges as they are preffered providers with them as well as with BC/BS.  They do not return my phone calls.  They were advised to call GEHA and they won't.  They ask me for money up front.  I see it that they owe me the $355.50 plus the double payments they have collected from BC/BS.