I've recently replaced my (sunken) S2 with a SS S4. This is my first time with LTE (via AT&T) and they still cannot get it setup. I keep receiving error code SVCEMSI22 when I try to "Set Up Cellular" in the app. I've called AT&T three or four times trying to get someone who knows what they are doing. Who else has experienced it and what did you have to do to resolve this issue? Thanks in advance!