FNB ACCOUNT FROZEN

I have a Business Account with FNB Since 2016 and I couldn’t pay monthly subscription from around September 2016 till March 2017 and My Account was put on hold since I was owing R5723.81 of which I still have Questions on how did I get to that amount. Well between 31 March 2017 and 05 April 2017 I had enough money to pay the above mentioned amount so I paid so that they could re-open my account cause they told me for them to re-open it, I must pay that debt. After paying in Centurion Mall Branch the Account was up and running again till on the 15th January 2019 when I was at the ATM trying to withdraw money and my account was frozen. I got into Kwaggafontein Branch to Inquire and that led me to go back to Centurion Mall to get Proof Of payment done in 2017. I couldn’t get help they promised to go through their record so they can find the proof and send it to their Legal Department. I have been calling them and also went back to the closest branch so I can communicate with them but I am still waiting on them to sort me out. Today is the 12 February 2019. Could you please assist me in resolving this issue coz this I definitely reflecting bad on my credit record and I paid 2 years ago