Username already in use

This is driving me nuts...

I am trying to edit a range of users' information in my admin area.

I simply want to insert addresses and phone numbers.

I can add teh info, but when I go to save the user, I get this annoying message:

Username already in use

I am then returned to the account I was trying to edit and all I can do is cancel, losing the added info.

Can anyone enlighten me. I imagine I am doing something wrong, but can't get to the bottom of it.

Thanks

Might be a redundant question to your issue, but do you have two or more users with the same username in your database? If so then the issue may be the Ajax username checker preventing you from making changes due to a duplicate username.

You can try turning off the ajax username checker and see if yo still get the same issue. Goto CB => Configuration => Registration tab and set the Ajax Username Checker to No. If you wish to use the checker, you cannot have duplicate usernames existing on your site.