Change the Data Plan, Lose the Voice Mail
A couple of weeks ago, I changed the data plan on my iPhone in order to get access to the mobile hotspot feature. Unbeknownst to me, doing that torched support for voicemail - the person who set up the new data plan left it off. It took me two phone calls to ATT to get that resolved - not because they were difficult, but because their back end provisioning sounds difficult. The tech support person I was just on the line with didn't understand why the voice mail was gone at first. Sounds to me like they need some simplification back there.