Why appering this error "invalid argument #2 (string expected, got Instance)"?

Hello. This should be a script to purchase a particular item through ProximityPrompt. The problem arises when I have to add a "player" variable to the path to take a certain amount of money from the player. It needs to work in "Script", not "LocalScript", so I need something like ".LocalPlayer" *mode for *"Script". I hope you understand the problem.

Error:

Workspace.ropebuy.Script:10: invalid argument #2 (string expected, got Instance). Error mark firsts "if" line as a problem.

Thanks.

local price = 200





script.Parent.item.ProximityPrompt.Triggered:Connect(function(player)


    if game.Players[player].Backpack.Money.Value >= price then

        game.Players[player].Backpack.Money.Value = game.Players[player].Backpack.Money.Value - price
        print("Buyed")

    end
    if game.Players[player].Backpack.Money.Value < price then

        script.Parent.error:Play()
        print("No money")
    end

end)