As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT GEAR DISAGREE AFTER TAKE OFF. DID QRH WITH MANUAL EXTENSION. GEAR CAME DOWN NORMALLY. (FLT#7432) FO: 12/21/2018 CLOSED LT MLG UPLOCK TARGET LOOSE. PS17GA AND PS18GA OUT OF RIG. TIGHTENED TARGET AND RE-RIGGED PROX SENSORSPS11GA, PS17GA AND PS18GA IAW AMM. PERFORMED EXTENSION/RETRACTION CHECK OF LANDING GEAR OPS CHECK GOOD AT THIS TIME.