Board Thread:General Discussion/@comment-33409689-20171223204725/@comment-30514476-20171223211000

They've logged into the game with Facebook. This is the only way to have a uniquely your own avatar picture. On launching the game, you'll see the play or log in with Facebook button.

Once you've logged in with Facebook, you can click on the avatar on the upper left corner and the first selection will be the Facebook one. Click on it to use as your new avatar.