Hello, and welcome.
My name is ***** ***** I will be glad to help.
When you make your reservations, be sure to put in your TSA Precheck number (Known Traveler Number or KTN) if you book online, and/or if you speak with a reservation agent at the airline or a or travel agent, give them the number to include in your reservation. If you fly frequently, make sure your KTN is in your profile with all airlines you fly.
As the previous expert mentioned, make sure your Precheck status has not expired and if it's over 5 years old, that would be the reason you didn't get it on this flight; however, in general, not every passenger is chosen to receive the expedited service on every flight, to enhance security measures.
I hope this helped you further.
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