I googled the area code and it is coming from the following area(s):
Brooklyn, Queens, Staten Island, New York
I just received a phone call with no message left either. When I called it back I got the same "The Nextel Customer you are trying to reach is not in service" message. Which I find odd since they just called.
When I did a reverse phone lookup, it states that it is coming from The Bronx.
Not sure if that is of help to anyone else having this issue.
This number just called me as well and hung up on the machine. Did as stated above, called back, and the number was no longer available "at this time". Growing tired of all this.