What goes in "Enter any 529 withdrawals not used for education..."

When you go thru State Taxes -> Changes from Fed -> 529 College savings account activities, the interview asks "Enter any 529 withdrawals not used for education".  It clarifies that it means non-qualified withdrawals ("additions") and contributions ("subtractions") for each year since 1998.

Do I enter my normal qualified contributions here?

I have been since TT started asking about it, and it pre-populates each year from last year's import.  After 20 years I read it more closely and it seems ambiguous. 

If I should not have entered qualifying contributions, what are the ramifications of my mistake?  

Finally, why does it always ask this and in the previous interview question it asks the redundant question of total contributions over the years?  Why doesn't it just add it up for me?

Thanks!