As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AFTER DEPARTURE, FLIGHT CREW NOTICED LT MLG DID NOT RETRACT. FLIGHT CREW ELECTED TO RETURN TO ORIGIN AIRPORT. NO EMERGENCY WAS DECLARED. ALTERNATE EXTENSION CARRIED OUT. ACFT FT LANDED AT ORIGIN AIRPORT. MAINTENANCE CARRIED HYDRAULIC PURGE OF AIR. ACFT RETURNED TO SERVICE NEXT DAY.