I’m getting the details but apparently there is literally a form to fill out and an internal check box that basically takes you off the radar. This is very much not legal advice. But I’m curious. And five years is a long time to not get bothered. I still think you technically owe and would likely get smashed in court but being off the radar is pretty good protection considering the goons at the govt are t going to do extra work typically and be like “he wasn’t wage slave #38467262 on my list last year I better look into that.”