Hello,
You will need to get the "mute" button working. Sometimes you can just slide it back-and-forth to free it up:
About the buttons and switches on your iPhone, iPad, or iPod touch
These are the standard steps for no sound:
- Is the side silent mute button on? Does any red show? Slide it back and fourth.
- How about the volume buttons? Is the volume very low? Move the buttons.
- Is Do Not Disturb on? Go to Settings > Focus > Do Not Disturb. Is it turned on? Check the times.
- Go to Settings > Sounds & Haptics. Check the Ringer and Alerts slider. Try changing the sound pattern for the type of alert.
- Go to Settings > Notifications. Is the app listed?
- Do other sounds work? What about phone calls?
- Volume summary: Adjust the volume on iPhone
- 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.