iPhone 17 Pro: Intermittent call/FaceTime issues

SealPing wrote:

Can’t make or receive phone calls or FaceTime on iPhone 17 Pro.

Call options stop working and I get no notifications of missed calls. Cellular service is fine and I can still send & receive texts and use data normally. This problems occurs randomly during the day even when I’m not using my phone. I’ve ran Apple Cellular Diagnostics from the Apple Support App which sometimes finds an issue with the eSIM and sometimes all test pass despite calls not working. Whenever I reset my network settings during the problem, the phone freezes at the Apple logo with the progress bar stuck at beginning. Restarting my phone does fix the issue but it keeps reoccurring every 1-4 days. I went to the Apple Store and they didn’t find a problem with my phone after running tests on it. They did a factory reset on my phone and the issue is still happening. I’ve contacted my carrier about this and they’ve found nothing wrong with my cellular service.

Device: iPhone 17 Pro (A3256) running iOS 26.5

Purchased in January, 2026, from an Apple Store in NY, USA.

You purchase in New York and where are you located now?

Click here If your call fails or you can’t receive calls on your iPhone - Apple Support

For FaceTime Calls: Audio and Video)

If you connect to Wifi, doesn't necessarily mean you are connected to the internet. --> Internet not available WiFi and Cellular … - Apple Community

Wi-Fi Assist is on by default. This will automatically switch to Cellular Data if the device is not connected to the internet.

About Wi-Fi Assist - Apple Support

Cellular Voice Calls vs. FaceTime Calls

• Cellular Voice Calls: These rely entirely on your mobile carrier’s cellular network. No internet connection is required. As long as your phone has a signal from the carrier’s towers, you can place and receive calls—even without Wi‑Fi or mobile data.
• FaceTime Calls: FaceTime is Apple’s proprietary VoIP (Voice over Internet Protocol) service. It requires an active internet connection—either Wi‑Fi or mobile data. Without internet access, FaceTime simply won’t work.

Key Difference

• Cellular calls = network‑based, independent of internet.
• FaceTime calls = internet‑based, dependent on Wi‑Fi or mobile data.

Extra Note

FaceTime is limited to Apple devices. You can’t directly call Android phones or landlines with FaceTime unless you generate a FaceTime link and the recipient opens it in a browser. Cellular calls, on the other hand, connect universally across all phones.