Hi.
I've been on O2 for a while and have recently added another SIM to my account for my wife. I had to speak to someone to enable WiFi calling on her account which was done successfully. However, she is repeatedly getting a pop up that says '4g calling has been turned off' and WiFi calling stops working. The WiFi calling phone setting has returned to 'off', and when an attempt is made to turn it back on, a message comes up saying that o2 need to be contacted to enable it. Checking in the device section of MyO2 tells me that both WiFi and 4g calling are on.
I've done a search on here and rebooting the phone has no effect. It just seems to restore itself after a day or two, only to repeat itself.
I've never lost WiFi calling on my phone so it's not a mast issue, and she has had this message both at home and other locations.
