Waiting more that 3 weeks for a refund, still no exact dated given

I made an error on the 26th January by paying more than R10 000.00 by accident in my Game card via EFT, which was mend to go for another creditor. I immediately contacted RSC to find out what I should do to get my refund. They told me which documents is needed. Since then I followed up on my refund on a daily basis. Today, two weeks later, I'm still waiting. The agent I spoke to now, said it should be in my account by Friday, which means it's almost 3 weeks I've been waiting for my refund. Working in finance myself this is totally unacceptable, I need that funds for other obligations I have! I am unable to speak to a manager, every time I speak to another agent, and all they can say is it will be escalated!