Samsung Destroyed My Device Under Warranty, Without My Consent

I recently sent my device, under warranty, to Samsung for a repair and without my consent, they ended up destroying it! Even though their policy states that if they can't fix it, then they should replace it with a new device – all I got from them was an insulting 300 TL gift card! That's even less than the original cost of my device which was 999 TL. When I refused their offer and asked to get my device back, I got the same answer - that it was destroyed. No explanation or solution whatsoever! This is totally unacceptable and so now I've made an application to Consumer Rights as I'm not going to let this go. Clearly, something is wrong if companies are allowed to get away with doing stuff like this.