Product faulty no reply

Hallo I have bought a mini vacuum cleaner in January, in April when I want to use it, the machine from the beginning every few seconds it goes of, then I let it cool then only can use it for a few minutes. The machine was everytime very hot. I have sent it back to the shop, I have cleaned it before taken it back, the lady at the shop, when she realized it was wet, she wanted to blame it on me, she didn't even want to listen further. She took the machine, she said someone will call me, but I haven't heard anything yet. It was at Checkers hyper Mayville Pretoria South Africa. Greetings Veranell