As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FINAL 9R ATL WHEN LANDING FLAPS WERE SELECTED 40, FLAP INDICATOR ONLY SHOWED FLAPS AT 15. EXECUTED A GO-AROUND AND TRIED TO RAISE FLAPS TO 10, FLAPS STAYED AT 15. ACCOMPLISHED 15 FLAP LANDING. TROUBLESHOT WITH NTF. REPLACED INDICATOR.