selling returned item as new

One of my customers bought a tv box two days ago. apart from no functionality in the netflix app with the remote, but perhaps the bigger issue is that my customer paid for something NEW. When i plugged it in there was someone else logged into netflix on a netflix account owned by someone named peter. This means that someone named peter bought this tv box and was not happy and returned it and then it was sold as a new item to my customer. This is just not how business is conducted and the south african consumer council should be made aware of this.