You cannot delete a cabin configuration that is assigned to an aircraft

[Ellid]

I’ve been trying to clear up some of the cabin configurations for aircraft I no longer operate D-9-41, 737-400, and 737-700, but when I delete the configurations I’m told “You cannot delete a cabin configuration that is assigned to an aircraft.” but the aircraft no longer exist in my fleet, is this because somewhere out there one of my old planes with the configuration is being used by someone else?

[Carde]

You hit the proverbial nail on the proverbial head. If the config is still in use you cannot delete it, quirk of the system, but a low priority for a fix atm.