I have a newly activiated Galaxy SIII and am having an issue with SMS and MMS. The phone number has a long history of being ported, most recently AT&T (2004-2012)->StraightTalk->Verizon.
I am able to send and receive both SMS and MMS with another Verizon phone, however, I am not able to receive either SMS or MMS from an AT&T phone. I was able to send an MMS to the AT&T phone, but I was not able to send SMS.
Any clues or help are appreciated!