BREACH OF CONTRACT AND NO REFUND OVER A YEAR

I signed up for a contract with MTN in 2012 then in 2014 i settled the contract and paid it in advance , the account was then settled in order though i paid an extra payment to MTN , MTN then did not automate my refund and i have been calling the call centre for the past year and they have not processed my refund and being taken from pillar to post which increases the frustration and they keep saying saying they will pay into my account and till tod date from July 2014 no refund has been processed and though if i was owing then for over a year they would have blacklisted me and put me on Legal. The service is beyond poor and would not want to trade with MTN anymore as they never put their customer 1st to them its all about receiving the payment and as for the csutomer they are not importantno customer retainment. I am still awaiting my repayment for the advcance amount i paid and nothing has been paid into my account. TOTAL BAD CUSTOMER EXPERIENCE.