ALWAYS RECEIVING A FAULTY DEVICE

I bought one of the latest ****le (Mobile Wi-Fi R209-Z) from Vodacom World. I set it up and it worked for 3 months, it then stopped. I then went to Sandton to see the data guys in the Vodacom Shop and they didn't know what to do with the ****le, they were not sure of what the issue was in the ****le and they referred me to the Repair Department. I had then mentioned the issue to them at the repair dept. and they told me that they don't repair but replace. They gave me a new one and i tried it at home and I faced the same issue again. I then went to Vodacom World and the main Technician there was also stuck in what the issue was so i went back to the repair dept the same thing happened where the ****le had the same problem. The Technician was very rude. This happened 4 times.I AM VERY DISAPPOINTED TO GET SUCH TERRIBLE SERVICE FROM SUCH A REPUTABLE COMPANY LIKE VODACOM - I want someone senior to get involved. When I asked them if we had to keep coming back and they mentioned i have to until my 2 years warrantee finishes. We fall under the onyx category in terms of the volume of business we give you. I EXPECT IMMEDIATE RESPONSE.