If you disagree with the insurance company's payment amount or whether or not they cover a service, contact the insurance company and ask them to review how the claim was processed.  If the insurance company finds that an error was made, note the information and whom you talked to at the insurance company.  Request an anticipated payment date and ask if they need anything from you.  If the insurance company feels the bill was paid correctly and you still disagree, find out from the insurance company what you need to do to file an "appeal" with them.  Filing an appeal will not guarantee that the insurance company will pay more on your bill, but the claim will be reviewed for reconsideration.