How to Cycle through 8 bricks, making 2 transparent every time?

So I have 8 bricks. 4 union and 4 parts. When you click the tool it should take away SR1 and SR11 first. Then on the second click it should take away SR2 and S22 etc for 4 clicks. However it only works on the first click then after that I can't click again! Help! Here is the code:

debounce = false
Tool = script.Parent
local player = game.Players.LocalPlayer
repeat wait() until player.Character ~= nil
local hum = player.Character:WaitForChild("Humanoid")

local animation = script.EatingAnimation 
local animation2 = script.HoldingAnimation 
local AnimTrack = hum:LoadAnimation(animation) 
local AnimTrack2 = hum:LoadAnimation(animation2)

Tool.Equipped:connect(function(mouse)
    mouse.Button1Down:connect(function()
if debounce == false then    
AnimTrack:Play()
debounce = true
if Tool.SR1.Transparency == 0 or Tool.SR11.Transparency == 0 then
    Tool.SR1.Transparency = 1
    Tool.SR11.Transparency = 1
else
    Tool.SR2.Transparency = 1
    Tool.SR22.Transparency = 1

if Tool.SR2.Transparency == 1 or Tool.SR22.Transparency == 1 then 
	Tool.SR3.Transparency = 1
    Tool.SR33.Transparency = 1
else
	Tool.SR4.Transparency = 1
    Tool.SR44.Transparency = 1
	end
wait(2.1)
debounce = false
    end
end
end)
end)

Tool.Equipped:connect(function()
if player:IsInGroup(2608221) then	
	AnimTrack2:Play()
	end
end)


Tool.Unequipped:connect(function()
    AnimTrack:Stop()
    AnimTrack2:Stop()
end)

I believe the problem lies within your conditionals on lines 17-30. You don't end the first one until line 33 which might not be what you want. Also, you were checking to see if SR2 and SR22 were transparent after making them transparent so it would've ran on the first try anyway. The way the script works now is it checks to see which is the highest number of transparent bricks and then makes the next higher one transparent.

debounce = false
Tool = script.Parent
local player = game.Players.LocalPlayer
repeat wait() until player.Character ~= nil
local hum = player.Character:WaitForChild("Humanoid")

local animation = script.EatingAnimation 
local animation2 = script.HoldingAnimation 
local AnimTrack = hum:LoadAnimation(animation) 
local AnimTrack2 = hum:LoadAnimation(animation2)

Tool.Equipped:connect(function(mouse)
	if player:IsInGroup(2608221) then   
   		AnimTrack2:Play()
   	end
	mouse.Button1Down:connect(function()
		if not debounce then   
			if Tool.SR4.Transparency ~= 1 and Tool.SR44.Transparency ~= 1 then 
				AnimTrack:Play()
			end
			debounce = true
			if Tool.SR3.Transparency == 1 or Tool.SR33.Transparency == 1 then
				Tool.SR4.Transparency = 1
    				Tool.SR44.Transparency = 1
			elseif Tool.SR2.Transparency == 1 or Tool.SR22.Transparency == 1 then 
    				Tool.SR3.Transparency = 1
    				Tool.SR33.Transparency = 1
			elseif Tool.SR1.Transparency == 1 or Tool.SR11.Transparency == 1 then
    				Tool.SR2.Transparency = 1
    				Tool.SR2.Transparency = 1
			else
    				Tool.SR1.Transparency = 1
    				Tool.SR11.Transparency = 1
			end
			wait(2.1)
			debounce = false
		end
	end)
end)

Tool.Unequipped:connect(function()
	AnimTrack:Stop()
	AnimTrack2:Stop()
end)