Double debit after I already paid and sent proof

When I app**** for Mtn router, I had to make a payment on their website (pos purchase) with my card. Received confirmation. Received router. Now for the last almost 2 months they say they didn't receive payment. After I sent all the proof it is still not sorted and tomorrow they are going to debit my Absa account DOUBLE! I have been talking to Mtn for the last almost 2 months on Facebook messenger. But still no closure. Now they want to take double my money tomorrow! How is it you can't find my payment which was done on YOUR WEBSITE through Pos payment with my Visa card? And no one is doing anything to rectify. If you double debit my account tomorrow, there will be hell to pay. I have spent endless hours trying to get this resolved, but you seem to be ***********! And or *****ulent!

ID ***

Ref for paymentt on application

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