Makro refusing a refund

I bought a USB-C to Display port adapter online to extend displays on my laptop , but it turned out that the USB-C connector does not fit on the port in the laptop. I notified Makro that I would like to change or get a refund as the adapter is not what I expected. After 2 weeks they came back and told me that because I removed the adapter from the packaging to test it , they will be rejecting my refund or exchange request. How the hell was I supposed to test the part in it's packaging? Which caring company will expect you to test something while in it's packaging and they are not even helping me with that answer. Mind you there is no seal that was broken as there was none , never even asked to see the packaging or the state of the adapter. I am disappointed in this brand which I have trusted for years.