iphone mal function

Hello,

These are the standard steps for no sound:

1) Is the side silent mute button on? Does any red show? Slide it back and fourth.

2) How about the volume buttons? Is the volume very low? Move the buttons.

3) Is Do Not Disturb on? Go to Settings > Focus > Do Not Disturb. Is it turned on? Check the times.

4) Go to Settings > Sounds & Haptics. Check the Ringer and Alerts slider.  Try changing the sound pattern for the type of alert.

5) Go to Settings > Notifications. Is the app listed?

6) Do other sounds work? What about phone calls? Music? 

7) Volume summary:  Adjust the volume on iPhone

8) Do you have an Apple watch? Many of the notifications will go to the watch instead of the phone.

Note: you can send text messages to yourself for testing purposes.

Good luck.

Hello,

Hmm, in that case, see this:

If you hear no sound or distorted sound from your iPhone, iPad, or iPod touch speaker

Good luck.