So I tried a download and was informed it was already in history. Couldn't find it.
The advice was to use --force.
What does that mean?
Use it where?
There was no further explanation.

It was explained to you in a previous thread how to do so in the Web PVR.

If you are using the command line version you simply (and literally) add --force to the command you are typing (separated by a single space from the other things you type and most easily added at the end).

https://forums.squarepenguin.co.uk/thread-1849.html

--force -> Force a re-download of something already downloaded.

You add it to the command you input to start the download.

e.g. get_iplayer --pid=wxyz1234 --force

or

get_iplayer --get 1234 --force

I assumed you were using the command line as I'm not sure you'd see that message in pvr mode.

If using PVR it is an option in the recording tab under search.