Maybe I just don't understand Wi-Fi calling and how it is supposed to work but I do not think mine is working correctly. I have AT&T and live in a part of the country that has VOLTE or HD LTE or whatever you want to call it. Anyway, on Monday AT&T activated this feature. I turned in on in the settings of my iPhone 6 Plus it didn't turn on immediately but I had read somewhere that it might take time so went on with my life and forgot about it until someone posted here showing what it looked like. So then I started searching Google trying to figure out why mine did not show as working. If I turn on Airplane Mode and then turn wifi back on it will come on and stay on for a while, even after I turn airplane mode off. It then disappears. If I go into cellular and change the data setting to either off or data only, the wifi calling symbol will again appear and remain even after I re-engage voice and data. But after a while it goes away again. I have reset network settings, turned the phone off, done a hard boot, nothing changes. Is this normal and if not, any idea what is wrong and what I can do? Thanks for any thought you can give to this.