That was happening earlier this year, to people who used a "Supporting Details" (SD) worksheet to enter those numbers last year......and an empty SD sheet transferred into this year's file for that field.
The fix (if I recall right) was to switch to Forms Mode to make the entry.....go to the proper field in the form to enter the $$$, then either enter the $$ in the SD sheet that pops up, OR when the SD sheet opens, you can delete it entirely, and then then the interview will work properly when you go back to the interview.
At least that's what I recall.
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Yeah, some strange software bug, and I don't recall if any later updates were supposed to fix it.
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
