Hi again, Nicki.
I'm not sure if you received my answer, as you said you paid and did not receive an answer in your other question, so I'm resending it, here:
Hello, Nicki and welcome.
If you actually applied for and were approved for TSA Precheck, it is a randomized system, and not every approved passenger will receive it on every flight. That may explain why you received it on your outbound flight, but not your return flight. However, some people are 'given' TSA Precheck without applying for it, just as a courtesy and to see if they like the program, but the same rules will apply regarding 'random selection' for any flight.
In order to find out your KTN or Known Traveler Number for TSA Precheck, assuming you applied, paid, were interviewed and were approved, visit the website below, follow all directions to fill out your personal information or call Universal Enrollment Service at the phone number given:
Universal Enrollment Service: ***-***-****
I hope this helps.
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