Based on the error you are getting and the result that you see when editing the content on your representatives page there might be a problem with the content that you have on this page. There could also be a problem with the files that you are using. The first thing you should try to do is make a backup of your HTMLEditor files on the server, then re-upload these files to the server to see if there is a problem in the files themselves.
If you get the same result it would indicate that there is a problem with the content that you have added to the page. If this is the case you may need to go into your db into the contents to update it, removing it would probably be best. Please give this a try and let us know what the result is.