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. USED DOWNLOCK RELEASE TO RETRACT GEAR. RETURNED TO SEA. PUT AIRCRAFT ON JACKS AND SWUNG GEAR 20 TIMES. CLEANED CANNON PLUG CONNECTIONS AND PROXIMITY SENSORS IAW EMB MM 32-00-00. UNABLE TO DUPLICATE DISCREPANCY.