WiFi calling services

Cell C upgrade process. I had a Postpaid Pinnacle 250 contract that were upgraded 16/01/2019. On this contract I had the WiFi calling facility, I then upgraded to the Pinical 1 Gig package starting 17/01/2019. I experienced usage on the aitime minutes as I was under the impression that the WiFi calling is still in force. I have noticed that on my Feb 2019 statement I was charged for WiFi calling. I then consulted the Cell C branch in Polokwane regarding this. I was then informed that the WiFi calling are no longer in force and that I then should purchase the WiFi calling minutes package for R 199pm and that I will not be able to use the service. If this service was ended how can I still access it or getting charged for it if it is no longer available? Now the question is that at the time the contract were upgraded I was never informed that the service will end on the new contract. So the end result is that my airtime minutes get reduced when making calls as well as getting charged for WiFi calling??????