Surface Pro 9 Core i7 nightmare, Vodacom gave the courier the wrong laptop.

I upgraded my contract via the web. The bad service didn't start there however. First I went to the store. I asked for the Core i7 Surface Pro 9. The manager at the store sent me a contract for the Core i5 Surface Pro 8. So I had to get him to cancel the order before they could help me online. I asked for the Core i7 Surface Pro 9 online, I received it today and it is Core i5 Surface Pro 9 not the Core i7. Now I need to send it back which might take another 5 working days for Ram Couriers to get the machine from me which is not what I ordered. I have the papers to show that they sent me the wrong laptop. Once they have returned the wrong laptop, I need to make a new order for the same laptop... How do I know they'll get it right this time around?