allanrhodarmer said:

After the server migration, the name of my character was changed from the name I created when I started the game, to a completely different name that I have never used.  Has this happened to anyone else, and is there a way to change it back?

Thank you.

Above the game, click your new name:

A new browser tab/window will open. There, click on "Profile":

You'll see your profile data with "Edit" options. Click the one next to your name:

Note that you will see this change in the game only after you reload it.