See the below link. It says that the TBAS can only be taking twice, but I would email them to see if a waiver can be given to retest for a 3rd time. Also, have you acquired more flight time since you took the test? If so, email them a copy of your log book that reflects the new hours and it will be updated in a few days.
How do I update my flying hours ?
If you accumulate more flying hours after your initial PCSM score, you need to forward this information to the PCSM Program Office. Scan the left and right sides, including total, of the last page of your logbook. Email both the Commanders Letter and the log book pages to AFPC.PCSM@us.af.mil
Upon receipt of all correct documents, udates are entered into the system within 1 business day. See Update Flying Hours
How do I update my AFOQT scores ?
If you retake the AFOQT, your scores will normally be automatically forwarded to the PCSM office. However, if you feel there is a problem, you should contact the Program Office via email. Your PCSM score is calculated using the latest AFOQT Pilot or EPQT score on file, not necessarily the best. In other words, if you retake the AFOQT (or EPQT) and your Pilot score drops, your PCSM score will be adjusted accordingly.
TBAS Test/Retest Policy.
Candidates are allowed 2 attempts at the TBAS test. TBAS tests must have a minumum of 180 days between attempts.