Cell C 1TB Home Connecta

We bought a Home Connecta Flexi 1TB data deal in June, the deal was valid for 60 days. We read on their TnC that you can buy time to extend the bundle. We called 4 days before expiry to extend and the agent informed us that the data will automatically rol***** and even confidently said that if it didn't we must call in and it will be sorted. On the 14th of August we woke up to no internet connection and obviously called Cell C and the agent said the data should have rolled over so she logged a call. Monday we called to get feedback and then we were told the data was never meant to roll over?. Long story short, many back and forth phone calls, Cell C offers to give us 10GB,I mean a measly 10GB! Did I mention we still had 700GB of 1TB left! I just can't! And then afterwards they tell us, I mean after I told them about their own TnC, they tell us they would would have charged us R10 per Gig for extension. If we had known the charges we would have decided whether we extend or just buy another bundle. This is totally not acceptable Cell C, 10GB,really! We work from home, our kids are homeschooled so we need data and a lot of it, daily so Cell C please have this sorted our ASAP!