As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA - ABORTED TAKEOFF - FLT 0749 - DURING TAKEOFF AT SEA EN ROUTE FOR PHX AFTER TAKEOFF THRUST APPLIED RECEIVED AFT CARGO DOOR OPEN INDICATION ON ECAM, REJECTED TAKEOFF AT LOW SPEED AND RETURNED TO GATE. MAINTENANCE FOUND AFT CARGO DOOR HANDLE EXTENDED, RESECURED HANDLE AND ALL INDICATIONS RETURNED TO NORMAL.