Zero response

I paid R500 cash for electricity on Thursday. I sent the usual SSD message on Friday morning and received a reply that I had "no funds". I sent 3 emails and 1 SMS on Friday with NO RESPONSE. They have no call centre number so there is no way of talking to a real person to find out where the problem lies. I tried phoning Blue Telecoms after 16:00 on Friday to ask for help - big mistake as everyone had gone home! What can you do to get a response from these people who go out of their way to avoid assisting their customers? I will be without electricity for the whole weekend at least.