Unhappy with their service

I paid off SAHL on the 16th of September 2021, and the payment was diverted to another account, which is also an SAHL account, and I requested them to allocate the account to the correct account to settle my debt, and they have been telling me that they wont be able to assist me, the funny thing is they have helped me with this before, I don’t understand why this time they are not able to, as I was doing online banking, I added the account that they gave me as my recipient, but it diverted itself to a different account, which is still their account, and I don’t understand why that happened, but my issue is that, I know they can sort this out, since they bank with Standard bank and as I said, they have helped me with this before but they refuse to, I am so unhappy and will never take loan from them, clearly they don't assist in making the life of their clients easy even if they are able to.