Hello,
I have a Samsung Galaxy S21 and previously was able to use wifi calling. However, the last few months I have not been able to connect once I was out of celluar service.
I can confirm that my Koodo account has VoLTE Access added. I have restarted my phone and done all the updates. When I turn wifi calling on with data, it shows it is on, but when I test by turning on airplane mode, it says cannot set up wifi calling