You had a few issues on the page that I've corrected.
You needed an "update" button on the page to submit the form. Your update trigger had to be changed to use that form submission, and some of your bindings were set to the recordset, which doesn't make sense since it was updating to the existing value.
Finally I updated the default value of the html editor to come from the recordset if it has a value and put in the enter value message if it is blank.
Please download the file so you can see the changes.