I am having the same issue on my NL920 as well. It never used to this, but now every time i hit the phone icon, it pops up and asks me to enter the VVM password. The regular VM password was not working, so I reset the PW and tried that, after I enter, it tries to sync and then pops right back asking me to enter the PW again. So irritating. Tried calling ATT, but the the hold time is forever. Now they are closed.
Is anyone else experiencing this issue? what did you do to solve it?