I had problems with my UA miles posting to my US Airways account. I had my FF# on the reservation. Was credited for the departing flight to ORD, but not credited with the return. I had to send my BP to the US Airways office in FL. Four weeks later.....nada. So I sent it again. It took 5 more weeks to get them credited. Anymore, I make sure that each segment has my FF# on it before I board the plane. It takes too much time to try to get the credit afterward.