I just got a bill for $7,000.00!!!!!!!

My insurance has sent me a bill for $7,000.00 for the surgery in January!!! They claim my doctor did not submit the paperwork after it was approved in time. Now, what do I do?!!! I am NOT paying this freaking bill!!!!! We were planning to use Dr. Reyes again for my husband's surgery, but now..........

Sorry for the HIJACK Lou Ann. Kate, I thought you changed your user name? Kim