How do I stop this for loop from firing my function multiple times?

Hello, me again.

For the past few weeks, maybe even months, I've been working on a keycard door . I was trying all sorts of different stuff to make it work, but today I managed to get a major breakthrough. My code finally worked. It correctly detected a IntValue inside all of my 6 keycards and then acted on what Number the value was. However, In order to search through the entire backpack, I used a for loop . This now makes the function fire 6 times due to me having 6 keycards, and the door opens multiple times. This of course is not what I want. I want it to only fire once if the Localplayer is the possession of a valid keycard , and if not, then it will stay closed.

well enough talking and more scripting. Ive added alot of notes to my script to make the understandment a bit more easier. The following script is the part of my script that is causing the trouble. Here:

--------------------------------- The first Keycard Reader ------------------------
script.Parent.Parent.KeycardReader1.ProximityPrompt.Triggered:connect(function(tool)
	------------------------ checking for the value in the keycards --
	local check = tool.Backpack:GetChildren()
	for i = 1, #check do -- begin of loop
		local Card = check[i] 
		local Value = Card.Keycard.Value -- Crucial Value defining the clearance
		if Value == 5 or Value == 4 or Value == 3 then -- correct clearances 
			bool = false
			print("Valid")
			script.Parent.AccessGranted:play()
			script.Parent.Parent.Light1.brickColor = BrickColor.new("Bright green")
			script.Parent.Parent.Light2.brickColor = BrickColor.new("Bright green")
			openDoor()
			wait(1)
			script.Parent.Parent.Light1.brickColor = BrickColor.new("Bright red")
			script.Parent.Parent.Light2.brickColor = BrickColor.new("Bright red")
		elseif Value == 2 or Value == 1 then -- false clearances
			bool2 = false
			print ("Invalid")
			script.Parent.AccessDenied:play()
			wait(1)
		end
	end-- end of loop (loops 6 times due to 6 keycards)
end)

The reason I just do not simply put the for loop out of the function is because then the Locals of "Card" and "Value" will be unknown due it being a property of the for loop. My question being: How do i stop this for loop?

just for good measures, here is the entire script.

------------------ Tweenstuff, ignore this -----------
local TweenService = game:GetService("TweenService")							

local door = script.Parent

local tweenInfo = TweenInfo.new(
	2,
	Enum.EasingStyle.Quart,
	Enum.EasingDirection.InOut,
	0,
	false,
	0
)

local OpenGoal = {
	CFrame = door.CFrame * CFrame.new(0, 0, door.Size.Z)
}
local ClosedGoal = {
	CFrame = door.CFrame
}

local TweenOpen = TweenService:Create(door, tweenInfo, OpenGoal)
local TweenClosed = TweenService:Create(door, tweenInfo, ClosedGoal)

local bool = true
local bool2 = true
------------------------------------------------------------------------------------------------------
local clearance = { -- here i tried to define the correct and incorrect clearances which didnt use much. maybe you can do something with this 
	["1"] = false,
	["2"] = false,
	["3"] = false,
	["4"] = true, 
	["5"] = true, 
	["6"] = true,

}

------ Opening of the door ------- (no problems here)--------
function openDoor()
	script.Parent.Parent.KeycardReader1.ProximityPrompt.Enabled = false
	script.Parent.Parent.KeycardReader2.ProximityPrompt.Enabled = false
	script.Parent.DoorOpen:play()
	TweenOpen:Play()
	wait(3)
	TweenClosed:Play()
	script.Parent.DoorClose:Play()

	script.Parent.Parent.KeycardReader1.ProximityPrompt.Enabled = true
	script.Parent.Parent.KeycardReader2.ProximityPrompt.Enabled = true
end
----------------------------------------------------------------------------------
--------------------------------- The first Keycard Reader ------------------------
script.Parent.Parent.KeycardReader1.ProximityPrompt.Triggered:connect(function(tool)
	------------------------ checking for the value in the keycards --
	local check = tool.Backpack:GetChildren()
	for i = 1, #check do -- begin of loop
		local Card = check[i] 
		local Value = Card.Keycard.Value -- Crucial Value defining the clearance
		if Value == 5 or Value == 4 or Value == 3 then -- correct clearances 
			bool = false
			print("Valid")
			script.Parent.AccessGranted:play()
			script.Parent.Parent.Light1.brickColor = BrickColor.new("Bright green")
			script.Parent.Parent.Light2.brickColor = BrickColor.new("Bright green")
			openDoor()
			wait(1)
			script.Parent.Parent.Light1.brickColor = BrickColor.new("Bright red")
			script.Parent.Parent.Light2.brickColor = BrickColor.new("Bright red")
		elseif Value == 2 or Value == 1 then -- false clearances
			bool2 = false
			print ("Invalid")
			script.Parent.AccessDenied:play()
			wait(1)
		end
	end-- end of loop (loops 6 times due to 6 keycards)
end)

--------------------------------- The second Keycard Reader (You can ignore this its the same thing) ------------------------
script.Parent.Parent.KeycardReader2.ProximityPrompt.Triggered:connect(function(tool)
	------------------------ checking for the value in the keycards --
	local check = tool.Backpack:GetChildren()
	for i = 1, #check do -- begin of loop
		local Card = check[i] 
		local Value = Card.Keycard.Value -- Crucial Value defining the clearance
		if Value == 5 or Value == 4 or Value == 3 then -- Correct clearances
			bool = false
			print("Valid")
			script.Parent.AccessGranted:play()
			script.Parent.Parent.Light1.brickColor = BrickColor.new("Bright green")
			script.Parent.Parent.Light2.brickColor = BrickColor.new("Bright green")
			openDoor() 
			wait(1)
			script.Parent.Parent.Light1.brickColor = BrickColor.new("Bright red")
			script.Parent.Parent.Light2.brickColor = BrickColor.new("Bright red")
			bool = true
		elseif Value == 2 or Value == 1 then -- false clearances
			bool2 = false
			print("Invalid")
			script.Parent.AccessDenied:play()
			wait(1)
			bool2 = true
		end
	end -- end of loop (loops 6 times due to 6 Keycards)
end)

Help would be much appreaciated. I am grateful for just the smallest tip.