Unsatisfied with service

I bought a laptop from the incredible connections store branch based at the East Rand Mall. Used it a few times and it started to give me technical problems. I returned it to the store 3 times and everytime I get it back it still gives me the same technical problem. I finally returned it back for the fourth and they told me I will get credit back and take a new laptop of my own choice. It's been almost three months now that I've been waiting to get my credit back. So now I'm stuck with no laptop and no money back. I'm struggling with work, and frustrated by being taken back and forth with no positive result. The technical gentleman who is always assisting is Siyabonga. The manager who hardly even comes out from her office to sort out queries is Bridget. Please sort this matter out because even incredible connections head office does not seem to care