Terrible service, not the same service any more

I ordered a 49 inch TV from takealot and after an hour of using it, it started to just cycle through different colours. After trying a few troubleshooting methods we gave up and lodged a return, initially as a refund and then I asked for this to be changed to a replacement the following day. The courier didn't come on the promised day, then came a day late faith the wrong vehicle and then eventually, 4 days later, fetched it. Now they processed it as a refund which would be fine but the price has gone up, so we have to pay in to get the same TV and wait another week. I have phoned about 8 times and nothing has helped. They do not see that they are at fault due to their late collection.