"I filed form 5329 in 2020 and have an amount in line 48."
This means that you did not tell TurboTax that you withdrew the excess contributions by the due date of the 2020 return (May 17, 2021, I think?).
"I withdrew the excess contributions in 2021"
Now you are saying that you did withdraw the excess in 2021. When? Before May 17, 2021? If not, then when?
"received a 1099-SA showing a distribution of excess contributions."
Did you get this in 2021 or 2022?
"For some reason turbotax is showing this sum from line 48 of form 5329 as a Deduction on my HSA summary, instead of under "Excess employer contributions withdrawn" where I would expect it."
So was your excess equal to your HSA contributions? That is, were your entire HSA contributions declared to be in excess?
"It also shows up as a HSA contribution on the "Your tax breaks" page."
Where?
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