Selling non quality and damaged goods

I bought a Mobicel tablet 8 June 2020 from Ackermans in Ventersdorp. When I got home I wanted to charge it so that I can set it up. I realized that it wasnt charging as the charging pin and charger didnt make contact. On Tuesday 9 June 2020 I took it back and asked for a refund, because it wasnt even used. So they said no and instead offer me 2 other tablets that was not in sealed boxes and had scratches all over. I insisted on refund but they said i must choose one of the 2 offered. So I took the alcatel one. They didnt even check it in the store as the battery was to flat. At home I charged it for 2 or more hours. When I tried connecting and setting it up it gave me system errors. I couldnt do anything. 2 tablets 2 days both not working. This is surely a reason for refund. Today wednesday 10 june I called the call centre. They said i must add more money and buy a popular name brand. If i had the money i wouldve. So basically they are selling **** and they know it. And how do you offer second hand damaged goods to.customers? I hope someone will respond as i just want my money back .today