Dyson nightmare

Hi I purchased the Dyson online from Goinstantza in August. I was so disappointed that this product which is so expensive didn't work I contacted the company and they said I should send them videos of me doing my hair. They rep**** by saying I need to buy hair products to put in my hair for the Dyson to work. Nothing worked and it looked like a deadend. Until 2 weeks ago when I recieved a msg from them saying I must send it back and they will consider giving me a refund. I paid 7800.00 and they only gave me 3500..i hardly used it cos it didn't work they sent me a msg stating it was in a bad condition which is a lie I'm utterly disappointed with them