Takealot - Useless service!

I received a promotional voucher from ABSA for Takealot's birthday. If I spent R1500 at Takealot I would get R500 off. When it came to checkout, the takealot site would not allow me to insert the voucher code. So I paid the full R1500. I have contacted takealot numerous times on their contact site. 3 agents have emailed me back. I keep submitting the information they require, such as the emailer from ABSA etc. The issue never gets resolved. And when I complain again, a new agent contacts me, asking for the same information. Not getting anywhere with them and you cant contact them telephonically. Hopeless service