Looks to me like you put it in the wrong form. You're showing a button click event, which is on the first form, yes? You're setting the id value to be what it already is on that form IF the statement would evaluate to TRUE which it won't because it's not a new record on the first form.
Move the code to the opening form as was stated in post 4. If I'm wrong about where the code is, my apologies.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.