wooden axle
I launched with the docking port connected via VAB and tried to detach in orbit.
The aircraft was once determined to be destroyed, but when I returned to the aircraft from the tracking station, there was no damage and the detach option disappeared from the docking port.
buoyant parcel
had the same problem, though It happened to me after docking 2 separate vessels around the Mun
velvet rain
It's working for me : just do a quick save and reload it - vessel will be separated