I am trying to return a product that was bought from the makro website

I am trying to return a product that was bought from the makro website. I have mailed numerous times and I still have not received back a response. All I am asking is for the item to be collected and returned, but it seems that makro is incapable of doing just that. I am not even able to find a record of that order on the website which is even more concerning. I just need this item to be collected