Bradlows Connectfin Harassment and Incompetence

I purchased a refrigerator 2yrs ago from Bradlows Cleary Park PE the service at the branch was phenomenal. However my nightmare begun with the accounts department CONNECTFIN. They have the audacity to blame a customer for an error on their part. They mistakenly gave myself and another customer the same reference for eft payments. This from the get go caused havoc as it caused consistent confusion regarding payments. Due to this I decided to make larger payments so that I could get rid of this account ASAP. To my relief i was ecstatic to have paid up a few months earlier than what I was contracted to. Now a couple months later I start receiving calls that Im in arrears, Iv since sent my proof of payments to one of many agents that has been harassing me. This incompetence of the Accounts department has not only negatively affected my credit score but has caused an hindrance at my WORKPLACE due to their constant calls during my working hours. Now I could ignore this however I use my phone for business communication . If this is not an infringement on my consumer rights then I am baffled. This incompetence and harassment has resulted in me having to pursue legal aid. I have advised all friends and family to not get involved/purchase from any store using this finance/ACCOUNTS DEPARTMENT that Bradlows uses. I've calculated my installments over and over by checking my proof of payments and as a matter of fact have realised that im owed as iv paid in a surplus amount and since contacting them regarding this it all ended in the above scenario.How convenient