Samsung Bad Product & Customer Service

I recently got a Samsung Note 8 Mobile, screen burnt out after a month. I took it in to Samsung (The Grove) for assessment. A week later they phoned me and said I can come and put in the new screen. I waited for about an hour. The next day it started overheating again, I phoned Samsung head office, they said I must just follow the same procedure like the first time. I complaint and said, this is just costing me extra money ... fuel, parking ticket, data (everytime I lose everything, I have to re install all my apps every time). And it is my valuable time, for damage that is not caused by me. They answered me by saying "mam at least you dont have to book it in, you can just go to the Grove, they asses it, order the screen and will let you know when you can come back for the repairs (while you wait). Please note that this is the only branch with technicians on board. I went back that Friday, the technician assessed the phone and confirmed that the screen burnt out again, but he said that I should come back on a Sunday, it is just easier for them to order the screen in on a Sunday. I went back 3 weeks later on a Sunday. The manager was in the front desk .... I explained to her the situation, she had a very, very, very bad attitude with us, and them claimed that they dont do the repairs on site anymore, I need to book in the phone and it can take up to 6 weeks. I asked but how could you assist me 3 weeks ago with the same problem and now procedures has changed? She answered me by saying "procedures can change at any time". A while later the technician came in, and he wanted to help us, but the manager refused by telling him that we have to book in the phone. I then phoned Samsung head office, I spoke to a lady and asked her about the procedure, she wasnt aware of the new procedure. She referred me to a manager, I waited 4 days for that manager to give me the call, she never did. I phoned her 4 days later. She got me and the technician of The Grove branch on one line.... then she also got very rude with me and all of the sudden that was a new procedure at Samsung. I asked her to please put it on writing for me and e-mail it to me, she just answered me by telling me there is no need for her to do that for me, after 29minutes she put the phone down on me. I wanted to know why they could assist me 3 weeks before and how can procedure suddenly change in 3 weeks? Why should I buy another phone if the Note 8 wasnt my fault?