Black listed me after paying the requested amount

NRB was contacting me about my account with home choice. i requested that they debit the money i owe in monthly installments in September 2014 and provided my banking details. they failed to do so and called me back in November 2014 and advised me that im in additional arrears again which i refused to pay so they asked me to settle all the money i owe at once so i do not have to pay for these additional arrears, which i agreed to. They debited the money from my account on 30 December 2014. Last month they started calling me back and told me i am in arrears with my home choice account again and they have listed me in the beureu. I advised them of what happened and that they must check their call records. I am now unable to get credit anywhere.