MTN Overcharging me on a router contract.

I’ve just about had it with MTN,I took up a 3 years contract with them for a 10G Router on special which meant I will pay R339 monthly ,then they started charging me the normal price which is R519.50,on 3 occasions I have called them on those occasions to understand why I was overcharged,and why I am being sent letters that I owe them .

I was told I would be credited for it and I won’t have to pay until I’m fully reimbursed. Now for the 3rd time,when I called I was told I would be credited again and I won’t have to pay anything after they even suspended my router.

I actually want to cancel this contract,this is the worst service that I have ever received especially because it’s 3 occasions that it has happened and there has not been any resolution.

Now I have to make sure that I only have the amount they need to debit on my account so that if they want to take out R519.50,it doesn’t go through.

I’m switching to another network provider,I’m done with MTN.