What’s the plugin name? Once you know, use any FTP software to access the /plugins folder and find its folder. It’s the one related to the plugin name. Once you find it, click on it and go to /hooks folder. Download the files inside this folder and find the onde with the function name parseTextForEmail. You will notice that this file has 2 parameters in that function. It now has 3. Add a , (comma) and what I posted above. Save and re upload the file.
If you never did that, you better ask someone to do it for you.