Yes, there have been a number of similar complaints. How did you pay the tax that was due? If you paid by direct debit, was the payment taken out of your bank account? If so, you should be able to reply to the IRS notice with a copy of the bank transaction record, showing that the payment was made. Read the entire notice carefully, and follow the instructions in the notice for how to respond. Send your response by certified mail with a return receipt, and be sure to respond by the deadline in the notice.