Approved application but debit mandate issues on capitec side

I'm at my wits end with this bank. I'll never refer them to anybody. Did a credit card application 5 times in 3 days which affects my credit score. All 5 applications were approved but they always having issues submitting the debit mandate and nobody reverts back to me pertaining a solution but each time I call they rather tell me that I have to redo the application. What sorcery is this. They keep on escalating but no feedback is given.