My phone doesn’t ring for incoming calls

Check to see that the Silent switch is not set to ON. Silent switch is located on the Top Left Sideof your iPhone. Open Settings ➔ Sounds & Haptics ➔ Ringer and Alerts : Make sure this is not set to OFF or too Low. Set Change with Buttons to OFF

If still isn't working try these suggestions provided my Alex Foley

1. Check to see that the Silent switch is not set to ON. Silent switch is located on the Top Left Sideof your iPhone.
2. Open Settings ➔ Sounds & Haptics ➔ Ringer and Alerts : Make sure this is not set to OFF or too Low. Set Change with Buttons to OFF. Below that Make sure that there is a Ringtone selected.
3. Check to see that Silence Unknown Callers is set to OFF. Open Settings ➔ Phone ➔ Silence Unknown Callers : Set this to OFF
4. Make sure that a ringer sound is assigned. Open Settings ➔ Sounds & Haptics ➔ Ringtone : Ensure that a Ringtone is assigned here.
5. Check to see that Do Not Disturb is set to OFF. SWIPE DOWN from the TOP RIGHT CORNER of your screen. This will reveal the CONTROL CENTER. Find the FOCUS button (should be highlighted in white if Do Not Disturb is ON) and Tap on it. This should turn OFF Do Not Disturb.
6. If all of the above is OK on your iPhone then Try and Force Restart your iPhone EXACTLY as shown below and see whether that resolves the issue:

• Press and quickly release Volume UP button
• Press and quickly release Volume DOWN button
• Press and Hold the SIDE button until an Apple logo appears and then release the Side button (Can take up to 20 seconds. (DO NOT release Side Button when invited to Slide Power OFF). 

iPhone User Guide - Apple Support (CA)

If your iPhone 16 Pro Max isn't ringing for incoming calls, several settings or issues could be causing this. Here’s a checklist to troubleshoot and resolve it:

1. Check Silent Mode Switch

• The Ring/Silent switch on the left side of your iPhone might be set to silent. Flip the switch towards the screen to turn off silent mode (you should see the ring bell icon on-screen when it’s active).

2. Adjust Ringer Volume

• Go to Settings > Sounds & Haptics and ensure that Ringer and Alerts volume is turned up. You can also toggle Change with Buttons on to adjust the ringer volume with the side volume buttons.

3. Do Not Disturb or Focus Mode

• Open Control Center (swipe down from the top-right corner) and check if Do Not Disturb or another Focus mode is enabled. If any are active, tap to turn them off, as these modes silence incoming calls and notifications.

4. Check Contact-Specific Settings

• Make sure that you haven’t set custom silence or mute options for specific contacts. Open the Contacts app, select a contact, tap Edit, and check the Ringtone and Text Tone settings.

5. Disable Silence Unknown Callers

• If Silence Unknown Callers is on, calls from numbers not in your contacts may not ring. Go to Settings > Phone > Silence Unknown Callers and turn it off if it’s on.

6. Restart Your iPhone

• Sometimes, a simple restart can resolve issues. Hold down the Side button and Volume Up button simultaneously, then slide to power off. After a few seconds, turn your phone back on.

7. Check for Software Updates

• Go to Settings > General > Software Update to make sure your iPhone is on the latest version, as software bugs can sometimes cause issues with incoming call alerts.

8. Reset All Settings

• If none of the above helps, go to Settings > General > Reset > Reset All Settings. This won’t delete your data but will reset system settings like Wi-Fi passwords and sounds, which may help.

After trying these steps, your iPhone should ring for incoming calls. If it still doesn’t, there could be a hardware issue with the speaker, and visiting an Apple Store or authorized repair center may be necessary.