This just happened to me, one extra letter added to my child's surname by phone agent. I never noticed it on the email receipt until a few days before the trip. I called UA and asked about changing it, the agent she could do it, but it "took a few days". She strongly recommended doing nothing since it was so close to the day of travel, and "let them take care of it at the airport". I couldn't check her in on-line for the international flight into the US, because the passport didn't match. At the airport for the departure, the agent seemed to fiddle with the computer a bit more, but it was all good. Global Entry worked flawlessly.Obviously, whatever the agent did was just for that flight. He didn't correct the "ticket" because the name was still an issue on the return legs and we had to repeat the process.