@all4christ10 Start documenting. It's hard to prove impossibility.
You'd probably be in the tax court informal procedure, though, so no expenses and if you do your research you won't need a lawyer.
@fortruth73 Pro tip don't give up no trying to get a hold of the government.
Find whatever document resulted in an overpayment. You've probably missed an appeal deadline. Talk to a lawyer or accountant.