Anti service manager

Bought second hand washing machine, they refused to test it, when I got home it doesn't not work as I wanted. I returned within 7 days. I got the arrogant manager who tell me I can't do anything, they will book it for repairs. They still to test if the machine still working but it was not tested when I bought it how will they know if i was working or not. That branch sells damaged products b when u return they fight u.