Variable being found unknown from function?

local function Round()
	local roundStartTime = tick()
end

	repeat
		local currentTime = tick()
		local TimeSinceGameStarted = currentTime - roundStartTime
		CreateExplosionPartCopy()
		wait(0.25)
	until TimeSinceGameStarted > onTime
	
	wait(offTime)
	
end

In the second block of code, you should see the "local TimeSinceGameStarted = currentTime - roundStartTime" line 3

My script isn't working and studio says roundStartTime is an unknown global, underlined in blue.

Thanks in advance

The problem here is that you made a function to declare the variable. Lukeb50 is correct, scrap it.

The problem here is one thing, functions wont run UNLESS IT IS CALLED. You never called it again, just defined it. Of course, you could just add a line of code to call it, but there is no point scince you never use the fuction again

Use functions when you want code to be repeated.

essentially, remove local function Round() and it's corresponding end