Paying someone s debt

I visited capitec bank in groblersdal mall on the 1st August because i've made a wrong transfer to a wrong beneficiary I called that person whom ive send my money to and ask him to please transfer back my money his reply was he is not using that bank anymore and he still owe the bank sum money I went to the bank and ask for reversal or transfer to the right person Now the bank took my money and paid someone s debt with it and they said if i want my money back i have to open a case... So by the look of things i have to do their job open a case so that they can get the person who owe them money..Please am not working for capitec i just need my money back...