MTN *** *****ulant calls

********** , this number phoned me claiming they are from MTN. I had a mtn contract 4years back. Cancelled the contract after it has been paid in full. MTN didn't want to cancel the contract and kept on phoning with new contract offers on which I declined I don't want a new contract., I am with TELKOM and very happy with their service. The 2 year contract is paid up in full. The phone was blocked and then re-activated. The person who called on my TELKOM number, which I do not have a clue where they got it from, was rude and said they noticed the phone is re-activated and that MTN wants their phone back. They are coming to fetch the phone at my home. She didn't even want to give her name or from which mtn department she is calling from!!! Is this a legal act from MTN with this threat calls?? When I called MTN customer service asking for proof that my contract has been cancelled they couldn't provide me with it, only logged a query and just gave me a reference number to follow up in 5days! MTN is a **** people, they don't want you to opt out of their contracts, you must just pay and pay. Since when does a cellphone provider send people out to the customers residence to take back their phones??? Sorry MTN you are the worst network ever with your ***** calls offering contracts, and if you don't take a contract, and mention you are with TELKOM they want the old phone back????!!! THIS CANNOT BE LEGAL!!! I NEED ANSWERS!