This is a bug that is current as of the 6/18/13 build. To work around this issue, please try these steps:
- Open up the Alliance settings option as the Alliance leader.
- Make what changes you wish to make.
- Change your Alliance name as well.
- After those changes go into effect, do a second change, where you change your Alliance name back.
- Please note that this may not work if another Alliance and you share the same name! In that case, you will not be able to change your name back to the original.
We are working on a permanent fix to this issue. Once it is fixed, we will let everyone know in our build notes.