Sound volume decreases when not in vicinity of radio. Not working.. Any help? [UNSOLVED]

It's been a while since I have last scripted (up to around a year) and now trying to get back into it by developing the script below. This script is placed under a transparent, CanCollide = false, sphere part. What I am trying to do is when the character is no longer touching the part (or within the sphere part), the volume of the sound decreases to 0 and then the sound pauses. I don't know what I am doing wrong. Perhaps someone can provide useful insight.

function onTouch(hit)
    local px = hit.Position.X
    local rx = script.Parent.Position.X 
    local py = hit.Position.Y
    local ry = script.Parent.Position.Y
    local pz = hit.Position.Z
    local rz = script.Parent.Position.Z
    local tx = math.abs((px)-(rx))
    local ty = math.abs((py)-(ry))
    local tz = math.abs((pz)-(rz))
    local z = game.Players:GetPlayerFromCharacter(hit.Parent)
    if tx > 20 then
        print("tx is" .. tx)
        for i=0, 1, 0.1 do
            wait(0.2)
            z.PlayerGui.Sound.Volume = (z.PlayerGui.Sound.Volume)-0.1
        end
        z.Parent.Parent.Sound:Pause()
    end
    if ty > 20 then
        print("ty is" .. ty)
        for i=0, 1, 0.1 do
            wait(0.2)
            z.PlayerGui.Sound.Volume = (z.PlayerGui.Sound.Volume)-0.1
        end
        z.Parent.Parent.Sound:Pause()
    end
    if tz > 20 then
        print("tz is" .. tz)
        for i=0, 1, 0.1 do
            wait(0.2)
            z.PlayerGui.Sound.Volume = (z.PlayerGui.Sound.Volume)-0.1
        end
    end
end

script.Parent.Touched:connect(onTouch)