As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLT - FLT 1021 - AFTER TAKEOFF FROM CLT, CAPTAIN REPORTED THE LEFT MAIN LANDING GEAR WOULD NOT RETRACT. FLIGHT RETURNED TO FIELD AT CLT AND LANDED WITHOUT FURTHER INCIDENT. NO EMERGENCY WAS DECLARED. MAINTENANCE REMOVED AND REPLACED THE LEFT MAIN LANDING GEAR HYDRAULIC MODULE PER MM 32-32-61. OPERATIONAL CHECK AND LEAK CHECK GOOD.