Discovery Health - the yet to "Discover" client service

Discovery Health paid my doctor and me for the same claim. They admitted their mistake. I received a message from Discovery "You owe us money, call this number . . . ". Not, "We made a mistake, we need your help to rectify the problem". I call the number, spend 15 minutes with a call center agent, he then puts me on hold while he talks to his manager. After 30 minutes the call is dropped. So frustrating!!!