Bad after sales treatment from Incredible Connection

I bought Xiaomi Mi Stick at Southgate and had to take it back because it kept switching off and resetting itself. A week after having left it I decided to call the “technician “ who had supposedly booked it in as I had had no reference or communication from the store regarding the stick. Unathi was rude to me and even hung up on me after having told me that it’s booked in and there’s nothing more he can do for me and that the number that he put on his work email is his personal number and I have no business calling him. I emailed the head office regarding my problem and to date, no response 3 weeks later and I actually don’t know what is happening and don’t know who to ask for I all I know that stick could be sitting in Unathi’s desk drawer.