What was found
RETURN TO GATE-PRIME AIR REPORTED CARGO DOOR NOT CLOSED COMPLETELY. NO CARGO DOOR LIGHT ON. AFTER INSPECTION FOUND CARGO DOOR ALL SECURE. REPORTED ERROR PROBALY CAUSED BY MISSING PAINT/DARK STAIN. MTX GROUNDED ACFT AND INSPECTED, PERFORMED GVI OF ALL CARGO DOORS, VERIFIED ALL DOORS WERE AND ARE CLOSED. VERIFIED ALL DOOR INDICATIONS ARE NORMAL, DOORS CLOSED. A/C RELEASED FOR NORMAL OPERATIONS.