Complaint about a declined claim

I am writing to formally raise a complaint regarding an ATM deposit of R600 that I attempted to make at an ABSA ATM at Canal Walk. While I was in the process of making the deposit, the ATM suddenly indicated that the deposit option was no longer available. The transaction was being made for a burial society, and as soon as the issue occurred, I contacted ABSA and provided all the relevant information from the receipt I received. I am extremely disappointed that my claim has since been declined without any clear explanation or sufficient information regarding the reason for the decision. I believe I deserve a proper explanation of what happened to my money and why my claim was declined. Furthermore, I have attempted to contact ABSA several times to follow up on this matter, but unfortunately, my calls keep getting disconnected, which has made it extremely difficult to resolve the issue. I kindly request that this matter be investigated thoroughly and that I be provided with a clear explanation of the outcome of my claim, including the reason for the decline and the status of my R600 deposit.