Welcome to Vodafone Community
My wife and I have just moved house, sadly it has limited coverage. I had been with O2/BT Cellnet since the 1990s, having checked Vodafone's coverage checker we have started new contracts with Vodafone (purchased through CPW) and the new Samsung J6.
Before purchasing a quick google search confirmed the J6 (2018) supported wifi calling on Vodafones business page: https://www.vodafone.co.uk/business/business-mobile-plans/mobile-plan-features/vodafone-wi-fi-callin...
(it isn't listed on their personal page, outdated list???)
Sadly we don't have wifi calling in our handset settings, but having read other users on this forum with similar Samsung issues I called 191 hoping for a software update, but the representative has confirmed that the J6 is not supported for wifi calls. Who is right, the operative or the website?
Your Samsung Phone model isn't listed so at the moment Vodafone Calling Over Wi-Fi is not available.
Samsung – Galaxy A3 (2016 and 2017), A5 (2016 and 2017), J3 (2017), J5 (2016 and 2017), Galaxy S6, Galaxy S6 edge, Galaxy S6 edge plus, Galaxy S7, Galaxy S7 edge, Galaxy S8, Galaxy S8+, Galaxy Note8, Galaxy S9, Galaxy S9 plus, A8, XCover 4."
Have you considered the Vodafone Sure Signal that creates a 3g signal in the home that runs off Home Broadband. It costs a one off £69 for the device.
Just to add taking some info from your link.
Even if Carphone Warehouse had put you on a Business Contract Vodafone Calling Over Wi-Fi wouldn't still work.
"All the listed devices will support the Wi-Fi calling service when purchased directly from Vodafone.
Please note that phones purchased from other UK telecom providers are unlikely to support Vodafone Wi-Fi Calling (with the exception of iPhones, which should work regardless."
Current Phone > Samsung Note 20 5G - SM9860 Snapdragon.
Samsung One Ui 2.5 / Android 10.