Stamina goes negative when I wrote code not to?

My stamina script is going haywire, and I can't find my error so I can't learn from my mistakes, Can you guys help me?

RunService.RenderStepped:Connect(function()
	local maxstamina = 9
	local StartingStamina = 0
 
	print(timeyouahavebeenrunning)
	if Userinputservice:IsKeyDown(Enum.KeyCode.LeftShift) and humanoid.MoveDirection.Magnitude > 0  and Debounce == true then

		
		if  timeyouahavebeenrunning >= maxstamina then
				local Debounce = false
		else
			humanoid.WalkSpeed = 23
			camera.FieldOfView = 80
			RunService.RenderStepped:Connect(RunningEffect)
			while wait(1) do

				timeyouahavebeenrunning = timeyouahavebeenrunning + 1
				if  timeyouahavebeenrunning >= maxstamina then
					break
					
				end
			end
		end
	else
		if timeyouahavebeenrunning <= StartingStamina then
			local Debouce = true
		else
			humanoid.WalkSpeed = 16
			camera.FieldOfView = 70
			RunService.RenderStepped:Connect(updateBobbleEffect)
			if timeyouahavebeenrunning < maxstamina then
				repeat
					wait(1)
					timeyouahavebeenrunning = timeyouahavebeenrunning - 1
				until humanoid.MoveDirection.Magnitude > 0 and Userinputservice:IsKeyDown(Enum.KeyCode.LeftShift)
				
				if humanoid.MoveDirection.Magnitude > 0 and Userinputservice:IsKeyDown(Enum.KeyCode.LeftShift) then
					local Debounce = true
				end

			else
				while wait(1) do
					timeyouahavebeenrunning = timeyouahavebeenrunning - 1
					if  timeyouahavebeenrunning <= StartingStamina then
						local Debounce = true
						break

					end
				end
					
			end
		end
		
	end
end)

At lines 10, 26, 38, and 45, change "local Debounce" to "Debounce".

When you add local, it creates a local variable that only the current code block can change/read, therefore it doesn't change the Debounce used at line 6.