My new blackberry 9800. No texting and phone calls = = This is China's system. There is also the display of China mobile characters, and there is also a signal. What should I do-~

First of all, are you sure your mobile phone is unlocked? Try changing a card and see if you can make a phone call or send a text message. If not, watch the online tutorial and unlock it yourself. Secondly, if you are sure it has been unlocked, set the network to 2G and see if you can send short messages or something. If yes, it means that the machine card does not match and needs to be replaced. I guess you used a 3G card. See if it's what I said. If the second situation is a little troublesome, you can't say it clearly in a few words.