Don’t send a check and don’t file a return. When the IRS asks you about it tell them you did and they must have lost it in a computer crash. Everyone now knows that they have no backup systems at all. lol
I am thinking of sending them a revised return with a full refund and claiming that Lois Lerner approved my request to be an exempt organization. I have the mail she sent around here somewhere....
The IRS must have a copy.