AARP Secure Horizons Generic drug ripoff Oklahoma City, Oklahoma

This is a Medicare Complete plan, which covers some prescription costs. Lipitor is now available in a generic form( as of 12/1/2011). However, Secure Horizons is charging the same co-pay as they do for brand name Lipitor. I called their customer service, and as usual the telephone rep could not answer my question as to this charge. The rep then puts you on hold until their phone system disconnects you several minutes later. This has happened to me several times in past. Their operating procedure seems to be if they can not answer the question, just hang up on the customer.