I am onto going to look for it right now but there was state official removed from office after he was elected because he was latter found to be ineligible. You can’t impeach an illegal office holder.
That’s how I remember it too. Wasn’t he just arrested/thrown in jail. Sort of like a person practicing medicine without a license
Thomas Moodie was elected governor of North Dakota, and after inaugurated was found to be ineligible by the State Supreme Court. He was removed from office by the court, and I believe everything he had done while in office was vacated.