Humana review: Medical coverage

My wife's Psychiatrist monitors her medication after she had an allergic reaction to Penicillin. I was assured by the agent that Medication management was covered by our present policy. After a week stay in the hospital she was put on medications which are monitored by Dr. Joseph Danial, MD, B.C. Psychiatrist. Dr. Danial is no longer takes our insurance coverage as he is in a private practice. I sent the Health Benefits Claim forms to Humana. I received no response that they were received, second after I called 30 days later; they said they lost the original bills which they then required me to send in with a copy of the claims form. A Humana agent assisted me in filling out to make sure it was completed correctly on the phone. I faxed copies to them which I always make to them at a cost of $8.00 and they said they could not read them. I then sent certified mail perfect copies of the claim form and bills. The four bills for $125.00 each or $500.00 were sent and We have Humana Choice PPO which means they should reimburse me $100.00 dollars for each bill. I have been getting the run around and meanwhile I am out now as I filed an additional claim of $250.00 for two more visits. for Medication Management. I am only responsible for 20% of the bill according to the agent.

I am 78 years old and my wife is 68 years old and we are on a fixed income. What can we do at this point?