Bidorbuy's protection act is useless

Bid or Buy Claim to have consumers protected which is not true, I won a bid online. Only to find out that the laptop I bid on was not what I saw in pictures, the laptop was broken and didn’t deserve to be sold on any platform. The seller used online photos to advertise the laptop which in my opinion is a false adverti*****t. I lodged a complaint and requested a refund thus they claim to have buyers protection act. When i paid for the laptop like always do i used Bid or Buy's account. To get a refund they're telling me that i must speak to the seller myself because he wants to pay me back in installments so we must speak and make an arrangement. Why must I accept that when i paid in full, hence Bidorbuy does not allow installments. So why don’t Bidorbuy pay me back and deal with the seller ? isn’t that what the buyers protection act must do ?