This seems to happen a lot:
Change a config on a phone button, or add a user to a paging greop, hit apply config, you get this message with a greyed out "Apply All Change" button;
Your changes have not been applied to the device.
You can continue to make changes on other pages, then click the button below to apply all changes
I see purple flags next to the sections I made changes to, but not amount of changes corrects the condition.
the only way to recover is to log out and start over...