As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING APPROACH WHEN FLAPS SELECTED TO FLAPS 1 THE LEADING EDGE SLAT DISAGREE LIGHT ILLUMINATED. FOLLOWED NON NORMAL AND LANDED WITH FLAP 20. RESET SYSTEM AND OPS CKD. FLAPS AND SLATS AND PERFORMED FIM 27-51-00. FOUND NO FAULTS SYSTEM OK.