ATM ERROR - No Refund

On the 11th August 2020 at about 18h15 i was at Chri Hani mall Vosloorus to do a cash deposit at an FNB ATM, where I counted my cash an stacked it in Two thousand on top of the ATM, and it was a sum of 6 thousand brands in total and loaded it in the machine and the machine brought back a 200 rand note back and showed 5,800.00 rands on the screen, and before concluding my deposit I pressed re-try note, went on counting some more notes I still had left, that was a total of 2,200.00 rands and put it in the machine then the machine never concluded my initial transaction instead disabled the deposit function and printed out a ATM slip that said my transaction was unsuccessful, and I turned towards the banks Cameras to show my face and tried to indicate that I had a problem and went on taking the ATM and the Slip a picture. I tried calling the customer care where I got a response from the voice prompts that they work from 9am to 4pm. I went to the bank the next day on the 12th August 2020 and they made me fill in a dispute form and they told me that my complaint will be investigated and it will take 72hours to be resolved, and when that is concluded my money will be deposited back in to my Account, to my surprise on the 13th August 2020 only a sum of 2,200.00 was deposited back into my Account. So went back to alert them and the response I got was that the surplus that they got from the machine was only that 2,200.00. So I am still short of the sum of 5,800.00 that I'm still awaiting till to date.