I received a customs letter about a year ago, the first time I had ever tried an IOP.

I figured for roughly $50 worth of Xanax, I would toss it in the trashcan and write it off, and thats just what I did.

Nothing came of it, and that is my understanding of the usual outcome of the letters when they are ignored - nothing.

Exactly like Imago said, just shrug and write it off as a life experience - and yeah I hadn't even thought of that, but if it is a reputable IOP, they typically have some sort of policy about resending if you can provide a customs letter, so thats worth considering too.

Either way don't worry about it.