WiFi calling is a feature on WiFi-enabled smartphones that allows users to make calls using WiFi networks.
To enable WiFi calling on an iPhone, ensure your network carrier supports the feature and your iPhone has a stable WiFi connection.
To enable WiFi calling on iPhone, go to the Settings app, tap on Phone, scroll to WiFi Calling, and enable the toggle for WiFi Calling on This iPhone.
If WiFi calling is not working, try restarting your iPhone, connecting to a different WiFi network, ensuring software is up to date, or resetting network settings.