Frustrated and confused

I was telecommunication by a lady whom sold me 80g data bundles with ruata for special of R149.00. when the product came it was now 2simcards and some other bundles not what I was signed up for and The bill ccontract R526.00 that is ruining my account it keeps on adding every month.i never agreed on this could somebody please assist argently because nobody want to be incharge anymore.i want to TERMINATE this contract.. when I spoke to customer service they said it was done but nothing has been done till this far.