Open Settings App > Connections > Wi-Fi Calling
Make sure Wi-Fi Calling is turned on.

  • If you see a direct Wi-Fi calling option, select it. 
  • Alternatively, tap on "Internet" or "SIMs" or "SIM card" settings and look for Wi-Fi calling there. 
  • Some phones may require you to go into "Calls" and then find the Wi-Fi calling option. 
  • Check with your carrier: Ensure that your mobile carrier supports Wi-Fi calling.
    Use the search bar: If you can't find the setting, use the search bar at the top of the Settings app and search for "Wi-Fi Calling". 
  • Confirm your connection: Make sure your phone is connected to a Wi-Fi network, which is indicated by the Wi-Fi signal in your status bar. 
  • Test the feature: Enable airplane mode, then turn Wi-Fi back on and try making a call to see if it works over Wi-Fi.