How to remove commas when converting files to tag names?

I am using:

%discnumber%$replace($lower($replace($num(%track%,2)-%artist%-%title%, ,_)),'',)

It's been so long since I created it I am not sure how to remove commas also when converting, what would I add to remove commas in the file name. Thank you!

$replace($num(%track%,2)-%artist%-%title%, ,_,',',#)
would replace the comma with a #.

Pleased note that this works for Convert>Tag-Filename but not for Convert>Filename -Tag.
(It is not quite clear to me which direction you want to take)

I am converting tag to file name sorry I said it wrong. I am trying to just remove the commas, currently it makes the file name people,_places,_things.mp3 I want it to make the file name people_places_things.mp3

Try:
$replace($num(%track%,2)-%artist%-%title%, ,_,',',)

%discnumber%$replace($lower($replace($num(%track%,2)-%artist%-%title%, ,_,',',)

says syntax error, I just tried replacing my current string with what you had though.

I think I have it already removing apostrophes I also wanted to add commas

You have not closed the outer $replace() brackets ...
%discnumber%$lower($replace($num(%track%,2)-%artist%-%title%, ,_,'',,',',))
I am not sure about the benefit of the double $replace() - so I removed that.

In my first post I did not change anything about that. The apostrophes in my suggestion escaped the commas which otherwise would separate parameters.

Thanks, I believe this works! I am not sure why I had a double $replace either, I made this like 10 years ago and haven't touched it since haha I probably just added things until it worked and left it alone. Thank you so much!