Cancellation of contract

On the 28th of January 2016 I cancelled my contract with eduloan as I realized that I won't be able to afford it and thus had other means to pay my outstanding tuition, I went to the University of Johannesburg Kingsway as I had app**** there, there was a lady called Bonolo whom with so much contention told me I had to write a cancellation letter and a certified ID of which I gave in on the 28th, I asked her for a proof of cancellation and she promised me that within a couple of days I will get it, today I called headed five and they told me that the account is still active and I will have to pay the interest. Why must I pay when I cancelled the loan and their stuff was the one that's in the fault because they have an attitude even when I was asking her about the terms of my contract she gave me an attitude. I need to escalate this matter as always institutions that claim to assist us in financial matters they end up exploiting us.