A:Answer Hi there, we are sorry to hear what happened. If the message memory full displays on the Digital Voice Recorder, then there is insufficient space left in the memory for recording. It will be necessary to erase some of the previous messages before you will be able to continue recording. However, if the unit continues to display memory full even after deleting messages from the unit, you will need to format Digital Voice Recorder.
https://docs.sony.com/release//Manual_4573933621.pdf
Regards,
Erin