As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED A GEAR DISAGREE MESSAGE UPON RETRACTION AFTER TAKEOFF. CREW RETURNED TO CLT AND LANDED WITHOUT INCIDENT. MAINTENANCE REMOVED AND REPLACED THE PROXIMITY SENSOR ELECTRONIC UNIT IN ACCORDANCE WITH THE AIRCRAFT MAINTENANCE MANUAL. OPERATIONAL CHECKS WERE PERFORMED. AIRCRAFT WAS RELEASED FOR SERVICE.