Selling ****** goods

I bought a phone on Groupon last year. sumsung galaxy s5 32gig. After much delay it was eventually delivered, however, i had issues recently with it and when i took it in to Sumsung to get fixed. I was told that it is blaclisted and had been ******. How can you guys sell me a ****** phone. Trying to get hold of you is a mission to resolve this. Can someone get back to me ASAP.