Lack of service

I have ordered and received a router from the MTN online shop. It has now been 3 weeks and the router is still not working. I went to a MTN store, but there was nobody who waa able to help me. I hane phoned numerous times, but they do not answer the phones after 17:00 or over the weekend. I have written numerous emails after which I get an apology but nothing else. Nobody at MYN is interested in actually solving the priblem.