How to Enable Wi-Fi Calling on a Cell Phone
When your iPhone has a low cellular signal, use Wi-Fi Calling to make and receive calls through a Wi-Fi network.
On your iPhone, go to Settings > Cellular.
If your iPhone has Dual SIM, choose a line (below Cellular Plans).
Tap Wi-Fi Calling, then turn on Wi-Fi Calling on This iPhone.
Enter or confirm your address for emergency services.
Note: Emergency calls on your iPhone are routed through cellular service when available. In the event that cellular service isn’t available, and you have enabled Wi-Fi Calling, emergency calls may be made over Wi-Fi, and your device’s location information may be used for emergency calls to aid response efforts, regardless of whether you enable Location Services. Some carriers may use the address you registered with the carrier when signing up for Wi-Fi Calling as your location. When connected to Wi-Fi calling, your iPhone may not receive emergency alerts.
- Apps icon > Settings > Advanced Calling.
- Tap Wi-Fi Calling.
- Tap When Roaming.
- Tap Prefer Wi-Fi.
If the above steps did not work for your android, please try these
- Open the Phone app .
- Tap More Settings.
- Tap Calls.
- Tap Wi-Fi calling. If you don't see this option, it’s because your carrier doesn’t support this feature.
- You can use Wi-Fi calling without a service on some carriers.
- If your carrier doesn't offer Wi-Fi calling, you can still do so through a voice over IP service.