Have been getting pre-check 95% of the time for the last two years, based soley on EXP tier on AA (I assume). Was informed I had to formally buy in ($85) and did so a few weeks ago, then input the KT number into my AA profile when it arrived in the mail. First trip since then today, no pre-check icon on my AA mobile BP. Stop at the front desk at BNA, they confirm the KTN is in my profile. Agent inputs it into my record, bingo, suddenly BP prints with pre-check icon. Agent says shouldn't need to do that, it should automatically populate. Anyone having a similar issue? Do I need to manually input the number into each record, for each flight? Is it a TSA issue or an airline issue? (If I ask them they will blame each other.) Thanks.