As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED L1 DOOR HANDLE CREPT UP APPROX. 1" IN FLT. NO COCKPIT INDICATION + NO ABNORMAL AIR NOISE FROM L1 DOOR . INSPECTED L1 DOOR HANDLE, LOCKS, & STOPS-ALL NORMAL. REMOVED DOOR HANDLE TRIM & FOUND INSULATION SLIPPED DOWN TO HANDLE, RESECURED. DOOR LOCKS NORMAL. OPS GOOD PER B737-900 AMM 52-10 (6233331).