Yes! Since last night, 2/29/2012, I have not been able to connect to the 4g network. I try to update my email or basically anything else and it says I need a network connection to preform that activity. I can still send and recieve texts though... don't know about phone calls, though I have tried to call *228 and it pops up with another weird message and never does anything.
don't ever use *228 from a 4g device. it can possibly toast your sim card. when you dial that it isn't even supposed to let you try to update the prl in this fashion form a 4g device. the sim does these updates automatically.
can either of you get data if you force your device to 3g?
i use an app called "LTE On/Off" only because it's quicker and easier than going through settings. however, you should be able to go to your menu-->settings-->wireless&networks-->radio info.
this is how to get there from my tbolt, but each device is a little bit different. once you find where to go on your device, you want to change it from "CDMA + LTE/EvDo auto" to "CDMA auto (PRL)." this will leave it on 3g and will not even look for 4g. this will also significantly improve your battery. you can always switch it back if you want to use 4g. i don't know if this will help, but it's worth trying.
Well I figured out how to do it but I didn't seem to help. I even power cycled my phone after changing the setting and nothing. I have had this happen before but usually power cycyling fixes it but I have done that several time today and nothing. Even removed and then replaced the battery and the sim card still no data. I have bars can still text but nothing else it seems.