As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE NOSE LANDING GEAR WOULD NOT RETRACT AFTER TAKEOFF FROM IAH. QRH PROCEDURES WERE COMPLIED WITH AND THE AIRCRAFT WAS RETURNED TO IAH WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE FOUND THE NOSE STRUT FLAT. THE NOSE STRUT WAS REPLACED AND SERVICED IAW MM 32-21-17. OPERATIONAL CHECKS WERE GOOD.