False advertising and refusing to acknowledge their mistake, apparently it is MY mistake

I upgraded my cellphone contract with Cell C in January this year. I went into their website first to see what was on offer so that I could choose the package that I wanted to upgrade to. I went onto the site and went to "Plans", then "Hot Deals". I am a fan of Huawei so I filtered the results to show only Huawei phones. I then saw a package that was put together by Cell C, for Huawei P10 Light with a Smart Data 5GB plan (5GB Anytime data + 10GB Nite data + Unlimited* Wi-Fi Calling minutes + Link up to 14 SIMs).

I called the call centre and they completed the upgrade for me and I received my new phone a few days later, all good so far.

I tried to "set up" WIFI calling on the phone a few weeks ago so that I could start using this function as the plan I took does not include any free minutes. Also I am going overseas later this year and this functionality is perfect for that (one of the reasons I took this plan). I couldn't get it right. Since then I have called in multiple times and to try and get this done and been advised that no set up was required I just have to ensure that I am connected to WIFI. I still did not see any WIFI calling. The technical department then advised me that Cell C does not support the Huawei P10 Light for WIFI calling.

Since last week Monday I have been calling to complain and ask Cell C how we are going to resolve the issue that I have been sold something that I have not been given, i.e. Unlimited fee WIFI calling. After many calls and many arguments this is their solution :-

It is my fault/problem that I can't perform WIFI calling as I "selected" a phone that is not capable of WIFI calling - I did not select the phone and pair it with this plan, it was already prepackaged like this by Cell C, the cellphone professionals.

I was supposed to ask if the phone is capable of WIFI calling, they never told me on the phone that I am going to get WIFI calling (the add in writing right infront of my face says I will) - I think Cell C should have advised me that although I am taking this package I would not be able to use the free WIFI calling minutes as this phone is not capable of it.

I then asked well how am I supposed to know that I should as this as it is assumed as this is what they are selling me. I was told to look at the specifications of the phone on the ad (there are 8 listed there) and see if the phone is capable of WIFI calling. So I said well if I look there it does not specify anything about WIFI calling. The response was, yes if it is not there it means that it does not have it (How am I supposed to know that, it is blank?????)

Any way, all I am asking is for Cell C to give me what they sold me and I am paying for each month. I am not trying to get out of the contract. If it means they have to swap the phone, or promise that in two months they will support WIFI calling on that phone, or any other solution they may suggest I am open to it. But to turn around and say that this is my fault and my problem they are not interested is just not acceptable to me. Ref ********** 188