DATA DISSAPPEARING

I have a contract with Vodacom to purchase 10GB of data per month, have had no problems up to 1st August 15, on the morning of the 2nd August I discovered we had no data, I telephoned in to find out why they had not put on my 10GB, had to log a service request, wait 48hrs and my reply was that it was because we used the data to update to windows 10!!!! we don't even have windows 10 and we don't want windows 10, so I again telephoned in as I was not happy with the outcome and was told we had to log another service request, wait 48hrs and again I got the exact same reponse!!! I telephoned in again two days ago as this is just not acceptable, Vodacom are trying to brush me under the carpet, as they admitted to having a technical problem over that period!! Sorry Vodacom but you are not going to make up a story just to get rid of me, its impossible to use 10GB of data in 1 day. Own up and give it back!!!