Cancellation of contract

I have ordered a Samsung j7 pro phone from telkom and when they delivered it, the screen colour was damaged when I put the phone on, so I phoned telkom about it and they told me they don't have stock of that phone which they can offer me something else and I took the Samsung j7 duo. Telkom then arranged courier it to pick up the damaged phone and after 3 weeks I got my new phone. So this is were it gets interesting, I have received my statement and then see I am going to pay for a contract which I never ask for and when I enquired about it they said it's the Samsung j7 pro contract. Telkom messed up and made a new contract for the Samsung j7 duo which was suppose to be a swap out for the current phone and when I want to cancel it telkom says to email them the waybill which the courier company picked up because they haven't received it. They then said I will get a refund of the money I will pay for that contract I am cancelling and it will take 21 days. And guess what I am still waiting and I am going to get debited this month again for a cell phone I don't have. I phoned almost everyday and I get told the same thing to email the waybill and it will take 24hrs to cancel it. All nonsense. At least I have proof of all the conversations with telkom on my phone. So I will be putting a stop order for the debit order they will be taking because I am frustrated about this. Basically giving them free money.