So I've had WiFi calling on forever but never really needed it or cared if it worked. I moved to a new building at work that has 0 cell service at all. WiFi is great but I get nothing on Verizon. I'm having the same bug on my P2XL on 9.0 as everyone else. The only way I can get WiFi calling to work is to toggle airplane mode and then cut wifi back on. This works flawlessly at my house... But not at work. It turns out you need at least a faint cell signal for it to work at all (I think).
Here's my cell signal at work. Notice in the first picture I'm in airplane mode with WiFi on. Messenger shows no connection at all. I can't call or text period (with my Verizon #). I took a screenshot of my sim status and surprisingly I can toggle back out of airplane mode and it stays the same. It shows IWLAN but because there's no Verizon service at all, it's as if they're blocking it from working.

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