Debit order account changed to an account I am not using without my request/permission

I called ABSA on the 14th of August to change my debit order date to the 26th of every month on my ABSA Funeral Plan ***. The debit order date was changed but ABSA also changed the debit order account number to Capitec, which I did not request. The debit order bounced at Capitec, and I was charged the Insufficient Funds Fee. I still don't understand why ABSA would change the debit order account, as I did not request this. Now I have to waste my time calling ABSA to correct this.