I have had several instances in different cities where my VZW iphone 5 has great coverage according to the signal bar, but it is not able to get on the internet, or receive mail. If I turn it on airplane mode, and back off, it usually fixes the issue. I know there has been some talk about this in the past. Is there a definitive explnation, or fix? I love my iPhone, but I hate having to do this in what seems like each time I go to use it.