Sounds like you don't have enough. UA is 30K each way (which you can get via transferring your Chase miles to United miles). DL is 60K minimum for one way or both ways (they have oneway awards but they are the same price as a roundtrip.) I suggest somehow getting an additional 10K Chase points (like by signing up for another credit card that offers Ultimate Reward points - Chase Freedom, Ink Bold) or use cash to buy the ticket.