Ignoring complaint after wrong product was delivered

The wrong product was sent to me after some time I needed to explain and prove that the product was wrong after I immediately requested the right one. I was told it would be sent if I am sure that I can't use the product I received. Almost three weeks later and still no product or pickup and now my messages are ignored and my calls are deleted. I still don't have my order although whatsapp shows business was online without responding.