What was found
FL 340, FWD CARGO NOT CLOSED WARNING ON ECAM. CABIN ALT WAS AT 300 FEET PER MINUTE. DESCENDED TO FL 100 & LIGHT EXTINGUISHED AT APPROXIMATELY 15,000'. CABIN ALT THEN STARTED TO DESCEND. INSPECTED FWD CARGO DOOR SEAL, NO DEFECTS NOTED. CLEANED & LUBED FWD CARGO DOOR SWITCH, NO BINDING NOTED. PERFORMED PRESSURIZATION TEST IAW AMM 05-53-00-00. OPERATIONS CHECKED GOOD, NO FAULTS FOUND. OK TO CONTINUE.