Upvote:4
Middle names are often an issue. If your wife has a middle name (and TSA knows that), the ticket must show the same middle name.
Even then, some airlines fail to transfer correctly. Both Delta and United print my name on the ticket as "Doe, JohnJack" - glueing first and middle name together. As a result, I never get TSA-Pre either, because that's obviously a mismatch for a TSA computers; sometimes when I go to the counter and ask them to correct this, they actually can fix it.
Not using the middle name when booking doesn't help either; as then it is no match either...
Btw, American and Lufthansa can handle that perfectly well, and TSA-Pre works every time there. It's just United and Delta, and it seems they couldn't care less about those issues - or would you fly another airline for that reason?
Another problem could be if you have a stored profile at the airline with slightly different data. I found once that my profile had a wrong birthday (after many years being correct, unclear why), and the airline transferred the birthday from the profile to TSA, not the (correct) one from the booked ticket.