Can't make loan payments - account not linked and error message "combi card has a prohibitive hold"

I am beyond frustrated with ABSA's poor service. I took out a Loan and agreed on debit orders. HOWEVER, the debit orders never happened. Just like that, I started getting calls from LAWYERS, saying my personal loan has been handed over. What?!

Okay, no problem, I'll pay it online. But I can't, because the loan account is not linked to my profile. I tried to link it, but keep getting the error message "Combi card has a prohibitive hold" - not specifying what this means or how to fix it. Whenever I try get support or search online, I'm just told I can pay the loan online or via mobile banking, BUT HOW DO I ACTUALLY DO THAT?

I also tried looking at the original loan documents they sent me, but there's no account number or payment information. So how on earth are you expecting me to pay my loan? Do you even want me to pay it back?