WiFi Calling (VoWifi) not Working

Reviving an old thread here instead of creating a new one, but I am pretty sure outbound wifi calling isn’t working. I have someone reporting that inbound wifi calls are received, they just can’t be dialed out.

Can anyone give any insights if they use wifi calling?

I did get this far before with another user, but in their case it was a Samsung device and Samsung doesn’t allow VoLTE / VoWifi on custom ROMs:

digging around on the internet and testing, I learned a bit but not enough to sort out if the issue is with my carrier, with iodé only, with Lineage in general, not having Google’s “Carrier Services” app installed, or other variations.

But to confirm if VoWifi is supported on a device, you can do this:

Dial *#*#4636#*#*. A testing menu will appear.
Tap Phone information
Tap 3 dots > IMS Service Status
You should see if VoWifi is available. For me it shows as unavailable but again this may be a carrier issue.

I get a result of Voice over Wifi: Unavailable so it may be that my carrier doesn’t support it. I did hear from at least 1 user they do show as Available can anyone confirm that it shows as Available for them, and if so have you attempted “Wifi only” calling using the normal dialer?