STORE SOLD US A FAULTY SAMSUNG 55' UHD

We purchased a Samsung 55' UHD TV on a Saturday the 23 January 2016, we installed it and we realized that there was a thin line at the bottom of the screen. on Monday the 25th January I went to the store to enquire about the price that was on the advert and the price that we paid and I mentioned the line on the TV to the store manager who sent me to the sales representative that assisted us. Unfortunately the salesman was not available and I explained the problem to another person that I found on the floor. I left my details and was told that the technician will come and have a look at the TV. few weeks went by with no feedback, I then went to the store and I was told that they will call. nothing was done and I went back again and I was told that we should bring back the TV and it will take 21 days to get the repairs done. How come this was not said in the beginning when the TV was only 2 days old? Why did they send me from pillar to post telling me that they will get a Samsung technician to call me? the service I have received is really saddening. we cant be without a TV for a month, this could have been avoided had they been eager to help me in the beginning.