My Pad Teleport won't make the pad lower down. (simple script)?

You can add and subtract vector3 values, so we can take advantage of that to make that work.

object.Position -= Vector3.new(0, 2.1, 0) -- this will subtract
object.Position += Vector3.new(0, 2.1, 0) -- this will add

If you want it to go up you need to add, and if you want it to go down, you subtract it. If it doesn't perfectly match, just try increasing the 2.1 value or decreasing, until it perfectly matches. So here is your script implementing that:

while true do
    script.Parent.Position -= Vector3.new(0, 2.1, 0) -- subtracting makes it lower, so we are using that
    wait(0.001)
end

Edit: it was going down forever because I was subtracting it from the same part, it needs to be subtracted from script.Parent.Parent.Give.Position. Here is the fixed (probably) script:

while true do
	script.Parent.Position = script.Parent.Parent.Give.Position - Vector3.new(0, 2.1, 0)
	wait(0.001)
end

In this one we don't need to do -= as it's not subracting from itself