Breach Of Contract

I had a 24 month top up contract with MTN which ended this month. On the contract I was to receive 200 airtime, 20 sms's and 200 MB monthly. This is what I paid for monthly without fail. Since May this year I did not receive my data which was allocated to me even though I paid my contract. I called the call center on the 23rd of this month and received a ref number:*** and was advised that someone would call me with regards to a refund as I had terminated the contract. I have received no call with regards to this and I cannot get through to the call center as my number is now prepaid. If I owed them I am sure their response would be very different, but because they owe me I cant get hold of them. MTN is the worst service provider ever!!!! quick to debit your account but can't keep up to their end of the contract. Thank goodness that this contract has ended what a *******!!!