Originally Posted by
javabytes
Airlines transmit information to TSA 72 hours out. I'm told if your KTN was not active at that time, that may be why you have not received Precheck. You might try asking them to remove your KTN, save, then put it back in, and save again. My understanding is changes made within the 72 hour period may trigger immediate validation, so if your KTN is active now, it may come back approved when they re-run the check.
I don't know if you must have your check-in cancelled and then re-check in for this to work, or if they have some other way of re-generating a boarding pass...
I suspect that if you add your KTN to a reservation before the KTN has been activated, it won't work.
BTW, with DL I've gotten PreCheck just by reprinting the boarding pass either at a kiosk or through an airport agent. This trick works especially well after an international arrival if either another airline issued the boarding passes or if you did yours through delta.dumb OLCI or with a "DL" agent at the originating international airport.