clearInterval

clearInterval stops a currently running Interval using it's ID

clearInterval takes 1 arguments, the timeout ID

local Age = 1
local interval = setInterval(function()
    Age = Age + 1
    print("You are " .. Age .. " years old")
end, 5) -- every 5 seconds this will print the current Age

delay(20) -- wait 20 seconds
clearInterval(interval) -- stop the current running interval
print("Final age " .. Age)