As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT NOT GROUNDED: PILOT REPROTS SMOKE IN LAVATORY ALERT IN FLIGHT: NO RESIDUE FOUND IN LAV. SUSPECT PASSENGER VAPING. MAINTENANCE COMPLIED WITH TSM 26-17-00-810-804A. NO EVIDENCE OF SMOKE CONDITION NOTED. CLEANED LAV SMOKE DETECTOR FLEECE FILTERS.