Welcome to Vodafone Community
This is not a question but it is intended to MAYBE clear up some confusion about WiFi calling using the S7 which has updated to Android 7 / Nougat.
I bought a used S7 locked to EE - it was NOT a Vodafone device and NOT bought from a Vodafone store. I unlocked it via EE (costs £9 but worth it) so I can use any SIM.
Switched to Vodafone Pay Monthly and searched for WiFi calling option. Many articles suggest the On/Off setting is in the main Settings menu somewhere but on my handset it is NOT there - I believe the Android 7 update removed / changed it.
I did find the setting as follows (these instructions are written so hopefully anyone can follow them!!)
To test / use the system I switched AIRPLANE mode on (to stop the normal mobile phone / SIM card making calls) and then switched WiFi on to connect to my home router. I can now call (and receive calls) via WiFi with absolutely no mobile phone signal.
I hope this is understandable and maybe helps someone who is struggling
Thank you for your insight.
When Calling Over WiFi was initially released Samsung Phones that we’re eligible to be used did have to be purchased from Vodafone but that has since changed.
A person may also find the Vodafone Support Page also helpful > How-do-I-set-up-Wi-Fi-Calling-on-an-Android-phone.
The Vodafone web-site is lying when it says Wi-Fi Calling is available, in my case, on a Samsung Galaxy S6 Edge which I did not purchase from Vodafone. Numerous calls to Vodafone Chat got absolutely nowhere. Nothing they could do could make the Wi-Fi Calling option appear in Phone Settings menus.
In the end, they referred me to my local Vodafone store where I was told that Wi-Fi Calling would only work if my phone had been bought from Vodafone.
What you may want to try, are these following steps. Sign into vodafone.co.uk, if not registered do so. Then select calling options for the number you need wifi calling enabled for. Disable it if it shows as enabled, otherwise follow next step.
Send "CALLING" by sms to 97888. After receiving sms to say that service is enabled, reboot device.
I've still got problems with my Galaxy S6 Edge after following your advice so I'll start off a new topic for this problem specifically.