Texture disappear once button clicked

[1101sky21e_JPN (Miyu)]

1. What do you want to achieve? I wanna make transparncy 1 when clicked after 1 more 0

2. What is the issue? Doesnt change the part after once.

Error at 17

local button = script.Parent
local open = false
local part1 = script.Parent.Parent.Parent.CLOSE
local part2 = script.Parent.Parent.Parent.OPEN

button.MouseClick:Connect(function(plr)
	if plr.TeamColor == BrickColor.new("Lapis") and open == false then
		part1.Transparency = 1
		part2.Transparency = 0
		for _, decal in pairs(part1:GetChildren()) do
			if decal:IsA('Texture') then
				decal.Transparency = 1
				for _, decal in pairs(part2:GetChildren()) do
					if decal:IsA('Texture') then
						decal.Transparency = 0
						open = true
						elseif plr.TeamColor == BrickColor.new("Lapis") and open == true then
							part1.Transparency = 0
							part2.Transparency = 1
							for _, decal in pairs(part2:GetChildren()) do
								if decal:IsA('Texture') then
									decal.Transparency = 1
									for _, decal in pairs(part1:GetChildren()) do
										if decal:IsA('Texture') then
											decal.Transparency = 0
											open = false
										end
									end
							end
						end
						end
				end
		end
			end
	end
end)```

[FroDev1002 (FroDev)]

Well for starters what is the error.
And second your code is not very readable for someone who does not know what it does so if you could leave comments on it that would help

[ZombieCrunchUK (Sunny_Bunny)]

Try this:

local button = script.Parent
local open = false
local part1 = script.Parent.Parent.Parent.CLOSE
local part2 = script.Parent.Parent.Parent.OPEN

button.MouseClick:Connect(function(plr)	
	if plr.TeamColor == BrickColor.new("Lapis") then
		if not open then
			part1.Transparency = 1
			part2.Transparency = 0
			for _, decal in pairs(part1:GetChildren()) do
				if decal:IsA('Texture') then decal.Transparency = 1 end
			end
			for _, decal in pairs(part2:GetChildren()) do
				if decal:IsA('Texture') then decal.Transparency = 0 end
			end
			open = true
		else
			part1.Transparency = 0
			part2.Transparency = 1
			for _, decal in pairs(part2:GetChildren()) do
				if decal:IsA('Texture') then decal.Transparency = 1 end
			end
			for _, decal in pairs(part1:GetChildren()) do
				if decal:IsA('Texture') then decal.Transparency = 0 end
			end
			open = false
		end
	end	
end)

Or if you want to make it a little more readable you could do something like this:

local button = script.Parent
local open = false
local part1 = script.Parent.Parent.Parent.CLOSE
local part2 = script.Parent.Parent.Parent.OPEN


local function ChangeTransparency(Frame, Transp)	
	Frame.Transparency = Transp
	for _, child in pairs(Frame:GetChildren()) do
		if child:IsA('Texture') then child.Transparency = Transp end
	end	
end

button.MouseClick:Connect(function(plr)	
	if plr.TeamColor == BrickColor.new("Lapis") then
		if not open then
			ChangeTransparency(part1, 1)
			ChangeTransparency(part2, 0)
			open = true
		else
			ChangeTransparency(part2, 1)
			ChangeTransparency(part1, 0)
			open = false
		end
	end	
end)

[FroDev1002 (FroDev)]

Lol yeah that is so much more readable!
Well you seem to know what your doing so I will leave you to it!