I'm having issues with my WiFi calling engaging, and staying engaged.
I am fully provisioned for WiFi calling from Rogers, as I've been trying to get this sorted for a while.
What occurs is that when I get onto a stable WiFi network, like at home, my phone will not automatically connect with WiFi calling. I will often have to reset my phone to get it to engage. When it is engaged, it will usually just stay this way for a few minutes to hours. It will randomly disconnect. At that point I will have to reset my phone again to get WiFi Calling to engage.
When WiFi calling is engaged, I can make calls without issue, I do not get dropped calls. The issue is not with dropped calls when using WiFi calling but with getting WiFi calling to actually connect and stay connected.
Of note, when I'm in Airplane mode with just WiFi on, then the connection to WiFi Calling remains stable, without random disconnects.
I'm not sure why this is happening. I've factory reset several times (including network settings), deleted apps, Rogers has reset my WiFi profile multiple times, nothing seems to make things work as they should (my wife's iPhone does not have this issue).
This happens on various WiFi networks, not just at home.
Of note, my Pixel 3 did the same thing. I was never able to get WiFi calling work properly as the above issues occurred.
I've contacted Google and they say this is a carrier issue and should be able to be resolved although they didn't give me any technical details as to what needs to be done.
I believe it may be due to your cellular signal level. Wifi calling is technically meant to help keep you connected when you have a poor signal. If you have a strong connection to the cellular network, wifi calling may not activate. When you put your phone in airplane mode, it is forced to remain connected.