Why can't my China Mobile SIM card send text messages?

Handling method of SMS sending failure: 1. When it is impossible to send short messages to only one customer, first confirm whether the receiver's mobile phone is in a normal state (such as arrears), or whether the short message function is temporarily turned off because there are too many short messages sent to the same customer. It is suggested to try again later, or you can check whether the information of the receiver is intact. The network where the receiver is located may be temporarily busy. Suggest trying again later. 2. When all customers can't send short messages, first confirm whether the number of the short message center is set correctly. If the mobile phone can't set up a short message center, let's see if downloading some software will affect the short message sending function. It is recommended to uninstall and try again.