Apple's mobile phone text message can't be sent out. What happened?

As one of the basic functions of mobile phones, SMS plays a very important role in our daily life. There are many reasons why it cannot be sent out, as follows:

1. Signal problem: When the cell phone signal is unstable or in the no signal area, it may lead to the failure of sending SMS. Make sure the cell phone signal is stable. If the signal is unstable, you can try to restart the phone or move to an area with good signal.

2. The number of SMS center is set incorrectly: If the number of SMS center is set incorrectly, the mobile phone will not be able to send SMS. Check whether the SMS center number in the mobile phone settings is correct. If you are not sure about the correct number, you can contact the mobile phone operator to get it.

3. Account or network setting problem: If the iMessage account is set incorrectly or there is a network problem, it may also lead to the failure of SMS sending. Make sure that the iMessage account is set correctly and the mobile phone network connection is normal. You can try to restart your phone or reset your network settings.