********** debit order

My installment was supposed to have ended in December with an amount of R350.00. HI-FI corp decided not to debit as they were looking to inflate my installment and prolong it. I sent them a mail quering the missed installment and I was rep**** and told a consultant will contact me to rectify the mistake but no one called me. In mid January I got a call telling me I have missed my last payment for December and that has caused my installment to fall into arrears which meant I had to pay more than the R350.00. Me not wanting to argue as I wanted nothing to do with them anymore I agreed that they can take that amount including the arrears. I received a call yesterday confirming that I will be making the payment today of which I agreed. This morning R436.17 was deducted from my account. However I then received a call from a consultant telling me my account is not yet paid up. After explaining that a debit order went of in the morning,I was told it would be updated the following day and I would be able to get a paid up letter at my nearest store. Later on in the day I received a call again from HI-FI corp wanting to arrange a payment of which O explained that the debit order went off. The agent assured me the account would be updated and that a paid up letter would be issued at my nearest store,and apologised for contacting me. In the evening just before 7pm a debit order for R436.23 went off for the same reference again. I tried calling their call centre only to find out they have closed already. I am truly disgusted at HI-FI corp for the service they have given me. It has been a 3 year contract of hell whereby they would just debit whenever they felt like and whatever amount they felt like devoting. My initial installment was R621.21 however they took a total amount of R872.40,how they got to that amount I really don't know. I kept on telling them everytime they would contact me that what they doing is ***** cause they were not living up to our contractual agreement. Whenever there were changes they would just initiate without customer consent. I am really disgusted at HI-FI corp and I really hope and pray people stop buying from them as they do not care about customers but themselves. The worst customer service ever.