Very poor customer service

If I could rate my experience with 0 star rating I would cause this one star is way too much for the service I got . Yesterday (23th March 2018) I went to Game Pavilion to return my Samsung UHD 55' Smart TV which just went blank and I had bought it last year in April. Luckily the same salesman who is the representative/promoter of Samsung (his name is Calvin) who helped me with the purchase, was the one on duty. So when I got there he was helping one customer with a purchase and he said he will check out the TV when he is done with that one customer. And I waited Over 25 minutes and mind you he was now helping other customers who had came after me. Fortunately the guy who works for Game store came to my rescue since he could see I've been standing for way too long and Calvin was just disinterested in helping me and he went from helping those customers who came after me to speaking on the phone right in front of me. What kind of service is this? and when I reported him to the Game store manager he was called and he had " I don't care attitude" I'm seriously so dissatisfied with the service I got from Calvin and this is no way to treat any customer.