Over 10 working days and orders still not delivered

I placed 2 orders, one on the 23rd of November and the other on the 24th of November. They have been stuck on "With Courier" since the 26th and the 25th of November respectively until now. I believe that both my orders have exceeded the 5-7 days delivery. It is now the 10th working day going to the 11th working day tomorrow. I have been emailing the customer support for the past 7 days. However, i haven't received any response. When I call i keep getting different stories. I called on Sunday the 6th and spoke to a guy by the name of Riaan and i was told that my orders would be delivered on the 7th...i was obviously **** to.

I called in again today and spoke to a lady whose name i didn't even bother to pay attention to and she said my orders would be delivered on Friday...which is also obviously a lie.

What else should i do for my oders to be delivered?