What was found
AIRCRAFT WAS GNDED. AIR INTERRUPT, EMER NOT DECLARED, LANDING UNEVENTFUL & ACFT NOT OVERWEIGHT. DURING CLIMB, ACFT WOULD NOT PRESSURIZE. FOUND RUBBER DUCT CAME LOOSE ON LT PACK. SECURED DUCT ON LT PACK & ACCOMPLISHED LEAK & OPERATIONAL CHECK IAW AMM 21-00-00-501.