I still don't hear audio playing someone help?

Your debounce starts off false so the code is never run since you're looking for whether the debounce is true.

local mat = workspace.Part 
local debounce = false 
local hitm = mat.music
mat.Touched:Connect(function(hit)
    if hit.Parent:FindFirstChild("Torso") and debounce == false then
        debounce = true
        hitm:Play()
        wait(.5)
        hitm.Ended:Wait()
        debounce = false
    end
end)