No response for pre authorisation

My self and my doctor have had over 20 follows-ups with Libcare over a two month period and they simply don’t respond. My doctor has filled in all the necessary documentation and motivation, but Libcare does not acknowledge. The contact agents make promises to call back, but never do. I have written to the Principle Officer Tracey Unser who is as useless, with no acknowledge of numerous follow-ups. They are happy to take my monthly contribution to pay their own salaries though. Its seems that a complaint to the CMS is the only way to get them to do their jobs.