to my 2020 tax payment due. When I paid my 2020 taxes...they sent me a check saying I had already paid it. I thought that was strange. Then they started dinging me for not paying my Estimated Tax payment. I spent HOURS just on hold to get it resolved. I finally spoke with several agents. They were not a lot of help. I had to write a letter explaining everything. At the end of the day...I spent more time and effort fighting it than the $75 of penalty/interest for not paying it. I never did get it resolved and just gave in and paid the penalty. UGH! It still bugs me today.