Custom URL form: how to remove custom url

I have tried this, however when I press the pencil to change the name it adds my name into the line also. I do not want this to happen can this be deleted some how.

This feature automatically adds the name to the form URL, unfortunately, it would not be possible to create a custom URL of a form without adding the username.
In order to remove it, you can click on the undo icon next to the pencil:

Let us know if you need further assistance.