As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 4 LEADING EDGE FLAP WOULD NOT RETRACT ON FLAP RETRACTION, AFTER TAKEOFF. FLAP POSITION AMBER LIGHT REMAINS ILLUMINATED WHEN FLAPS AT ZERO. AIRCRAFT RETURNED TO MSP AND LANDED WITHOUT INCIDENT. MAINTENANCE FOUND SAFETY LOCK MISSING ON SWITCH. ADJUSTED BOLT AND INSTALLED NEW LOCK, GROUND TEST NORMAL.