I have been having problems for over two years. I ...

I have been having problems for over two years. I have filed many grievances and customer service is a joke.They say I should have a response in 7-10 days then I never receive a reply. I call back and they have no knowledge of the grievance or they are still working on it after a month. I have one that is going on two years. Billing is worse than customer service. I asked a billing/customer service representative if she had a supervisor and was told that she was as far as I could go. She can't be the upper management. Very disappointing. The coverage is fine but customer service and billing need immediate attention.