As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, RECEIVED PROX SYS FAULT 1. AFTERWARDS, GEAR UP WAS CALLED FOR AND PERFORMED. ALL THREE GEAR INDICATORS REMAINED GREEN. LANDING GEAR DID NOT RETRACT. GEAR DISAGREE WARNING MESSAGE. PERFORMED QRH. RTF. (FLT 3076) FO: 07/20/2018 CLOSED RIGGED PX22 IAW AMM. OPS CHECK GOOD AT THIS TIME.