To update the Add-on, first download the new version.

Then go to the Blender preference and from there select to the add-on preference, click on the"Install Update" button, navigate to the new version and install it (do not install by clicking on the blue button down, install with the big blue button in the side panel).

Done !!!

First select the vertice that is causing the problem.

Click "x" to delete that vertice, now you see a hole.

Select the loop of the hole then press "f" to fill the hole.

Now it should work as intended.