Blackberry z 10 can't send messages, Unicom card.

I suggest you test your Unicom card before changing your mobile phone. If not, there is something wrong with your mobile phone card. I suggest you change your mobile phone card in the business hall. In addition, if you send a lot of short messages recently, you may be blacklisted by the system. It is suggested that you need to bring valid documents to Unicom's own business hall. If it can be used normally, I suggest you reset the SMS center number in your mobile phone. Please refer to the following screenshot for specific setting parameters:

If it is not the above reasons, I suggest you call the local 100 10 to help you check.