Back in 1977 when my husband and I got married, not only did I not take his surname, I filled out the paperwork listing me as head of household since I had the most income. The idiot accountants who did the actual filings switched our names on the premise that a married woman cannot be head of household - something I still find objectionable.
What we didn't notice when we mailed off the forms and the check to the IRS was that the idiot accounts did NOT switch our social security numbers. So a little while later, we got a letter from the IRS saying that the SS #s were wrong - as you said, "there are apparently no human beings with full use of their brains employed at the IRS." We filled out the form they sent, putting the SS#s in the correct slots.
Then I got a letter from the Social Security Administration, asking why I had not notified them of my name change. It seems the IRS took C. S. Ziggy and husband Name Notziggy to mean that my name was now C. S. Notziggy - even though the names were fully spelled out on separate lines - and they told the SSA that it had changed. I wrote the SSA and told them I had NOT changed my name and it was (and still is) the name I was given at birth and would not be changing.
Forty fucking years and I am still having that argument with government officials. My name is the same as it always has been. The only thing that was simpler was getting my passport - though I did supply a copy of our marriage certificate, the passport people got my name right the first time around.
Oh, the idiot accountant firm only did our taxes that one year. The accoutant that I used for over twenty years and the one that "inherited" my business when he retired have always gotten things correct. They even know to send the bills to me and not to my husband.