It sounds like there is a disconnect between your doctor and the insurance company.  Set up an appointment with your doctor and then ask him to call the insurance company with you to find out what more info they need.  You may also want to include your company's HR Manager on this call.  If it looks like your insurance company is wrongfully denying your claim, even after your doctor has provided all of the required information, then contact the state board of insurance to file a claim against the provider for wrongfully denying the claim.  This process is free.  However, if you want assistance with the process, then you would have to hire your own attorney to assist you.  If you do need an attorney, find one that is experienced in dealing with insurance companies.  Many people tend to reach out to employment law attorneys because it relates to an employment benefit, but the issue is really a wrongful denial of a claim issue through an insurance carrier.