Demonscycle Sold me a defective brake master cylinder and wont replace it Pompano Beach Florida

purchased a set of handle bars with controls on them bought them in oct. 2012 did not install them until recent.when i tried to bleed the brake master cylinder it would not build pressure sent demoncycle an email told me to check the seals.i told them i should not have to check anything and i wanted a new one they told me too much time had passed and they wont take them back told them i just wanted a new master cylinder they told me they could sell me one i told them that i have already paid for a working one and thats what i would like no response from them.they have alot of negative feed back on the internet