As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: RIGHT AFTER GEAR RETRACTION GEAR NOT UPLOCKED ECAM FLIGHT CREW RECYCLED GEAR AND GEAR MESSAGE CLEARED. MAINTENANCE PLACED LEFT MAIN LANDING GEAR PROXIMITY SWITCH 21GA PER AMM 32-31-73. A SATISFACTORY OPERATIONAL CHECK WAS ACCOMPLISHED.