******** deduction to my account

I took out a loan with absa and was paying the instalment on monthly bases, I was in arrears and arranged with them to pay the arrears with the instalment over two months which was January and February 2020. End of March absa deducted the instalment plus arrears even though I was not in arrears anymore. I reversed the amount and called their loan department to explain what happened and asked for the account number to deposit the instalment since I reversed the amount they deducted which included arrears that no longer exists. To my suprise on the 24th of this month absa deducted 7800 from my account for personal loan and further decreased reversal amount to R250 on my online banking so I couldn't reverse the money. I am so disgusted by their conduct as I couldn't do whatever I planned to do during this lockdown because of them. Should they have checked their records they would have seen I am not behind with my instalment and deducted the correct amount, who gave them consent to go into my account and deduct such huge amount of money. I want my money back in my account as in yesterday and will be reporting their conduct as well as changing banks