WiFi calling stopped working Galaxy S20

[6thSense]

Hello,

After a recent software update earlier in December on my new (2mnths) old Galaxy S20, the WiFi calling has disappeared.

This is quite noticeable as there is NO mobile service where I live and it worked perfectly before with the symbol visible.

So I urgently need to get this back. It was working fine until the update. However, now I cannot find the option to enable or disable it in the settings drawer. Or in settings. Or anywhere.

A call to O2 resulted in the agent saying the option is on the account and to switch the phone off then on again after 24hrs. This has been done.

So has powering off and removing the sim. Perform a power cycle then replace the sim.

There is still no WiFi calling option.

The O2 helpline cannot seem to help so can the community forum step up to the plate?

Advice gratefully received.

Many thanks

[MI5 · Accepted solution]

@6thSense 

Turn off and remove SIM card.

Turn phone back on and wait for it to fully boot up, then replace the SIM with phone on.

WiFi calling will return.

[6thSense]

That did it. When I tried that last time I powered down again before inserting the sim. Inserting a sim with power on seems a little counter intuitive though. But thanks.