Data and Minutes that were forfeited

I am so angry with Mtn South Africa. I got a contract deal for two phones. I paid them off and I left the data and minutes. I didn't pay them for 1 month for data n minutes. And from there onwards I have never received anything from them. I thought I since owe them R250 let me go n pay it off n close the account. only to found that am being charged R1030. When I asked them why am being charged this amount. They told me, just because I was not receiving my data and minutes doesn't mean that am not getting changed for it. I asked if I pay the R1030 will I receive all my data that I have never received since June. I was told that, the data and minutes we forfeited I won't get anything. My question is who pays for something that they didn't receive and even if I do pay am still not gonna get it. This is *****, I can't pay for something I never got n I won't get even if I pay. R1030 is alot of money to just give it to someone. This is wrong very wrong. You give me Data and I pay for it. You don't give me data I won't pay. Fix this so that I can give u your 250.