Changing my contract type to less Gigs without me knowing

<p>After investigating why I am running out of 10 gigs of data so fast, I realised that you have changed my contract to only 5 gigs. Oringinally I signed up for 10gb + 10gb contract for R199, which for months you charged me R299 for. It took me forever to get that sorted out. Now I see that you have changed me to a 5gb+5gb contract. How can you do this to me again? This is highly *******. I have a signed document which I have kept my side of, by paying every month the amount agreed upon. I have never missed a payment but you feel free to just changed my contract? I want this fixed and I want the data that is owed to me payed back. This is breach of contract! I cannot wait to be done with Telkom. </p>