Takealot rejecting return of inacurate digital vernier

I recently bought a vernier for around R200 via Takealot. I found it to be inaccurate and sent it back. They rejected my return and refuse to reimburse me because I HAD USED IT. How else can one know if it is working? It is still in the condition that is was when I received it, including the box, the instructions etc. I then noticed that many of the reviewers on Takealot are complaining of the same thing. I spent over R10 000 in 2023. Now because they are being unfair, I will stop buying from them. I have an email trail that I can show anyone interested.