MTN changes TOP UP Data line to OPEN LINE

<p>Hello Peter,</p> <p> </p> <p>I have a 2G Top up data sim with MTN...After 2 years the contract was automatically changed to be anOPEN LINE....since I was used to being prompted when i need to top up,I did not realise that my line was now changed to be an open line!! Now MTN has debitted R2338.70 from my account...instead of the usual R159 that I signed up for.This is *****!!!!! I signed for a TOP UP and not an OPEN LINE.I am shocked to learn that they can just do this without consulting the customer.</p> <p> </p> <p>I want my money back,this is not right MTN!</p>