As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, LANDING GEAR WOULD NOT RETRACT. WHEELS APPEARED TO VISUALLY CYCLE LOCKED AND UNLOCKED. ECAM MESSAGE L-G NOT UPLOCKED. RECYCLED GEAR AND RETRACTED OK. *S/D* REPLACED SAFETY VALVE. SOLENOID WAS OVERHEATING. SHOP TEST INDICATED NON-OPERATING PILOT VALVE. TEARDOWN INDICATED SCORING ON PILOT VALVE SLIDE.