(Associated Press) – Boeing has refused to disclose who worked on the door plug that blew off a jetliner in January, according to the head of the agency that’s conducting the investigation.

ennifer Homendy, the chair of the National Transportation Board, also said Wednesday that Boeing has failed to turn over documentation around work on the plane — or whether records even exist.

Homendy calls it “absurd” that her investigators still don’t have that information two months after the blowout of a panel on an Alaska Airlines Boeing 737 Max 9 over Oregon.

The NTSB says critical bolts were missing after repair work on the plane.