Unhappy customer

I am not happy with takealot. I received an order that I bought online at takealot. I was not happy with the pan as it has dents. I requested an exchange and I advised that the pan will be collected on the 19th of May 2020. Since today they have not collected the package. I have been following up with them and no one is coming back to me. What am I supposed to do with the package as I am not happy with it. I want an exchange. I am very frustrated.