Why does Apple sometimes send text messages without sound?

This may be caused by the following reasons:

1, it may be that the phone has turned on silent mode. There is a mute button on the left side of the front of Apple's mobile phone, which will turn on the mute mode downward, and there is no sound when the message comes.

2. It may be that the phone has turned on the Do Not Disturb mode, so there is no sound within the set time, and it can be turned off in the settings.

3. Check whether the volume of the mobile phone is too low. If it is too low, you may not hear the sound.

4. Check whether the mobile phone has turned on message notification, enter the "Settings" of the mobile phone, click "Notification", click the application that needs to receive messages in the list, turn on "Allow notification" and turn on the switch behind "Sound".

5. In addition, you should turn on the notification of receiving new messages in the application. Take WeChat as an example, open WeChat, click "My" in the lower right corner, click "Settings", click "New Message Alert", and finally turn on the switch on the right side of "Notification of New Message Received".