get_iplayer Remux: Programme "already in history" error

[Xander Squier]

Hello 1&All,
We are trying to remux a raw recording using the Windows command:-

/get_iplayer --pid=b08bzzns --command-tv="ffmpeg -i \""<filename>"\"
-c:v copy -c:a copy -y \""<dir>\<fileprefix>".mkv\""/
This returns a programme "already in history" error necessitating the
--force option. The trouble is that using this results in a redownload
of the recording which is what we are trying to avoid.
Please help up see what we are missing - thanks.