Can somebody correct my error?

Im making a sword fighting game, and I want it so if the player is on a certain block, then they are allowed to fight eachother with swords. If they are not on the block, then do not allow them to fight.

This is my script:

wait()

SafeBrickName = "SafeZone"
DefaultDistance = 30

player = script.Parent.Parent
distnum = DefaultDistance
sorted = false

function MakeFF()
    if player.Character:FindFirstChild("ForceField") then
        RemoveFF()
    end
    local ff = Instance.new("ForceField")
    ff.Parent = player.Character
end

function RemoveFF()
    local fc = player.Character:GetChildren()
    for i = 1, #fc do
        if fc[i].Name == "ForceField" then
            fc[i]:Destroy()
        end
    end
end


while true do
    sorted = false
    local c = game.Workspace:GetChildren()
    for i = 1, #c do
        if c[i].Name == SafeBrickName and sorted == false then
            distnum = DefaultDistance
            local dist = (player.Character:FindFirstChild("Torso").Position - c[i].Position).magnitude
            if c[i]:FindFirstChild("Distance") ~= nil then
                distnum = c[i]:FindFirstChild("Distance").Value
            end
            if dist < distnum then
                MakeFF()
                sorted = true
            else
                if player.Character:FindFirstChild("ForceField") then
                    RemoveFF()
                end
            end
        end
    end
wait(3)