Fiddling with usernames can screw with the database (This has been noted when banning people) so that's probably the issue. If you aren't too desperate to change any of your homes then I'd wait till the end of the month when your username expires and returns to normal. Failing that, if you set the homes as a modified name and have changed it again since then you will need to return to that username to be able to modify your /homes. Hope that helps.