As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLOOR PANEL WAS REPAIRED AND EXISTING INSERTS IN FLOOR PANEL WERE LEFT INSIDE OLD CORE MATERIAL AND NEW SKINS WERE INSTALLED. THE OLD INSERTS INSIDE THE PANEL MAKE IT IMPOSSIBLE TO INSTALL NEW STYLE INSERTS THAT MUST GO THROUGH TOP ANDBOTTOM SKINS. TIME SINCE REPAIR 0:00.