What should I do if my mobile phone can't send a short message to a different number?

This has nothing to do with your mobile phone or mobile phone card. It's just that there is a problem with the mobile deployment system to prevent spam messages, which often leads to the accidental killing and filtering of inter-provincial messages, resulting in unsuccessful sending or successful sending but not receiving.

Call 10086 directly and transfer to manual customer service to complain. If they don't admit it, you can go to the mobile business hall to find their staff to solve it. Complain several times 10086, at least one of my friends does.