I asked Grok:
That’s a frustrating issue! When you’re on a FaceTime call and an incoming phone call causes it to disconnect, it’s likely due to how your iPhone handles call priority or a glitch in the system. Normally, you should see options like “End & Accept,” “Hold & Accept,” or “Decline” when a new call comes in, without dropping the FaceTime session entirely—unless something’s interfering.
Here’s what might be happening and how to address it:
- iOS Bug: Some users have reported this behavior, especially with certain iOS versions (like iOS 16 or earlier), where FaceTime drops unexpectedly when another call comes in, even if you try to decline it. Apple hasn’t fully acknowledged this as a widespread issue, but it’s popped up in forums since at least 2023.
- Network Conflict: If your FaceTime call is using Wi-Fi and the incoming call switches your phone to cellular data (or vice versa), a shaky connection might force the FaceTime session to drop.
- Settings Misconfiguration: Your call handling settings might not be optimized, or a feature like Wi-Fi Assist could be kicking in at the wrong time.
Quick Fixes to Try:
- Update iOS: Go to Settings > General > Software Update. As of March 27, 2025, the latest version should be iOS 18 or higher. Updates often patch bugs like this.
- Restart Your iPhone: A simple reboot can clear temporary glitches. Hold the power button (with volume down on newer models) until the slider appears, then restart.
- Check Wi-Fi Assist: Go to Settings > Cellular (or Mobile Data) > scroll to Wi-Fi Assist and turn it off. This stops your phone from switching networks mid-call, which might destabilize FaceTime.
- Reset Network Settings: If it’s a persistent issue, go to Settings > General > Transfer or Reset iPhone > Reset > Reset Network Settings. This clears Wi-Fi and cellular configs (you’ll need to re-enter Wi-Fi passwords).
- Test with Cellular Off: Turn off cellular data (Settings > Cellular > Cellular Data Off) and use FaceTime over Wi-Fi only. If it stops disconnecting, the issue might be a cellular handoff problem.
If none of these work, it could be worth contacting Apple Support, as it might be a deeper software quirk tied to your specific device or iOS version.