What should I do if my iPhone 6s cannot send text messages?

1. First of all, you need to confirm whether the current mobile network signal of iPhone is normal. If you are in some signal blind areas, such as elevators, you may encounter failure to send text messages.

2. If you confirm that there is no problem with the current mobile signal and making calls is normal, you can try to restart the iPhone at this time. You can press and hold the power button of the phone, slide it to turn it off, and then turn it on again.

3. If you still cannot send text messages after restarting, you can also try to restore the iPhone's network settings at this time. Solve it by restoring network settings in Settings-General-Restore list.

4. If it still doesn’t work after restoring the network settings, it is recommended to call the operator’s customer service and ask them to help check the data in the background of the mobile phone to see if there is a problem.