I thought movie p was free that why i download it, afterwards when i saw it i delete it?

but after 3 days i recieve email that i have to pay for it i was shock, i try to call costumer service but no answer, i delete movie p using system restore so far no pop up, do i have to call them and cancel movie p or let it go, im i obligated to pay them im afraid they aregoing to show up again im i legaly responsible,we have multiple account in 1 com im afraid they going to enter the other account what should i do, should i call a lawyer, pls help me, i didnt give any credit card bec i have non but im calling them to cancel my account if they demand payment should i pay them pls help me