Makro ***** policy

On the 27/12/2018 i bought an item at makro paying with my bank card of which i have a copy of my bank statement indicating the payment and i kept the receipt and the box. I have since return the item on the 30/08/ 2019 (faulty) which still falls within the gaurentee period and i was told that it will be send to a workshop to assess the fault and determine if it is a custormor fault which i know is a factory fault. The item; the slip and the box including my makro card number was supp****; now after 11 days makro are telling me i did not buy it with my makro card as the number dont respond. If you get a temporary card at the front desk and the *********** people did write down the number wrongly why is it my concern as i got all the prove that it was bought at makro. The argument now is the the makro card number; i have since bought a new item from a different store while makro resolve their return policy issues. i have now request makro to return the item so that i can fix it myself as they cant even tell me the status of the item. i will pesuade any person i know not to buy from makro this is my promise. I phone them today and said they phoning me back still waiting after 3 hrs.