Disgusting, dishonest service!

Last week a consultant kept calling me and insisting that my contract was due for an upgrade and that I must sign a new contract which will save me money. I kept telling her that I don't want to sign another contract yet as I don't need a new phone and I'm happy to stay on a month to month billing until I decide that I want a new phone. She insisted that at any moment if I needed a new phone I could just change the contract accordingly. She would not take no for an answer and eventually I told her to call me on another day and I went to the Mtn store to ask if what she told me was true and they said absolutely not - once I sign a new contract that is only airtime and data then I can't change it and get a new phone until the contract is finished. So, I decided that I would not sign a new contract and then - lo and behold, this morning I got an sms to inform me that my new contract has been approved! Apparently the only way that I can cancel this unwanted upgrade is to phone ********** and guess what - they NEVER answer the phone - EVER!!!!! I am absolutely appalled at this absolute disregard for customer service. How is it possible for a company to change your contract without your actually signing for it??? I eventually went to an Mtn store and the consultant shook her head and said that they get many customers complaining of the same thing and that the only thing she could do was to send an email to request a cancellation. I am absolutely disgusted!