Wha?!?

Shock! Amazement! Unprecedented in the annals of all of human history!
Two years ago I had made a mistake on my taxes, which I fixed pronto.
The IRS had not noticed my fix, my amended return and the money I'd sent when I
discovered my mistake. They started sending me letters demanding I pay more.
And...Now ...This!!!
Today I get a letter from the IRS telling me that they were in error, and that they apologise
for their mistake.
wow.