You don’t need to switch back, you just need to do some work on this text area plugin and have it configured properly to do what you want it to do.
In the meantime, this is quite easy for you to fix as admin, simply do the following:
1. Copy the entire post into notepad. That will remove all the users html formatting.
2. Copy the text from notepad and paste it back into the textarea and save the post.
ps you dont need to publish this just trying to help a little, sorry about the typos.