As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - FLT 3969 - PILOT REPORTED THAT AFTER TAKEOFF THE LANDING GEAR WOULD NOT RETRACT. THE AIRCRAFT RETURNED TO IAH AND LANDED WITHOUT INCIDENT. MAINTENANCE REMOVED AND REPLACED THE LEFT MAIN GEAR FORWARD PROXIMITY SWITCH, AND THE AIRCRAFT WAS RETURNED TO SERVICE. (M)