I got the Xphone from eBay, and found out that it's from AT&T and it's 4.2.2. Because I'm in Singapore now and using a different carrier. But, I found out that it can't connect to internet with Cellular but only can access internet with WiFi. So I update it to 4.4.2. But I still can't access to internet with cellular.
It's showed that already connected to 4G, signal is also very strong. But, just can't use internet without WiFi. The normal phone functions all are OK, I can call and SMS but just can'st use internet with Cellular.
Why is that happening? Anybody can help me?
Thanks a lot.