I have problems making WiFi Calls on my Google Pixel 8a

Slide two fingers downwards starting from the top of the screen.

Press the settings icon.

Press Network and Internet.

Press SIMs.

Press the name of the SIM.

Press Wi-Fi Calling.

Press the indicator next to 'Use Wi-Fi calling' to turn the function on or off.

Slide your finger upwards starting from the bottom of the screen to return to the home screen.

Slide two fingers downwards starting from the top of the screen.

Press the settings icon.

Press System.

Press Software updates. If a new software version is available, it's displayed. Follow the instructions on the screen to update the phone software.

Press and hold the Side key for about 30 seconds to restart your phone.