Recently delta.dumb and I managed easily to do something that should have been impossible. I successfully checked in for the first flight of a complicated itinerary and printed my boarding pass when the flight number on my reservation did not match the flight number on my ticket (as shown on the receipt). I discovered this by accident and was amazed. I also had visions of not being allowed to board at the airport in the morning or, worse, being trapped at my destination when I tried again to check in for a return flight where my reservation and my ticket did not match. In the case of the first flight, flight status said that the flight I had purchased--the one on my receipt--did not currently exist, while the last segment was a case of an existing flight that didn't go where I needed (not wanted) to go, in this case, TPA instead of MSP. After noticing the errors, I immediately called the DM line several times, using the "call back until you find someone who understands/helps/gives the answer you want" strategy. The first agent and her supervisor, both in SLC and sounding competent and professional, tried to tell me that it was no problem, even though the return was still an issue. The second tried to say that since I had already checked in, I should just get to the airport early (what I wanted to avoid with OLCI) in order to get a printout of my reservation and ticket from an agent. It wasn't at all clear to me why this might help. The third agent acknowledged why I was worried and initially said that nothing could be done as I had already checked in. When I reminded her that she could indeed un-check me in, she agreed to contact the international manual reissue desk. After about forty-five more minutes, I had a receipt that matched my plans and my reservation; I did not even lose my reserved seats. I was surprised first that delta.dumb was apparently willing to let me travel with an incorrect ticket and secondly that so many DL agents seemed to be so nonchalant and unconcerned about the situation, even after I explained it several times and had them agree that indeed, the ticket was wrong as it didn't match and this should normally cause trouble. Of course schedule changes were the culprits here, but it never occurred to me that I should routinely compare my tickets to my PNRs at regular intervals for every trip.