Jones11

I have a sony mini disc MZ-NH700 As I divided a track and press "stop" in order to save changes, it started to flash "System file writing" as it normally does, but it would not stop. Can you advise what I should do? If I unplug power, it might erase the recording and I am worried. It normally takes several seconds to edit but it is flashing "System file writing" for more than an hour...Any suggestions?