Cellular Data可以View Account，流量可以看到还剩200mb，但就是上不了网，显示：
Could not activate cellular data network
You are not subscribed to a cellular data service
按了ok后显示
Cellular Data Plan Usage
There is no data remaining on your current plan. Would you like to add more
data now? If you don't add now, you can do it later in Settings.
可是我这个月的200mb明明一点没用过啊...
