Did you make a IRA contribution or take a RMD from a IRA or 401K? 5329 is for extra tax like the 10% Early Withdrawal Penalty if you were under 59 1/2. Or if you did not take out enough for the RMD. OR if you made an excess IRA contribution.
Did you get a 1099R for any of those things? If you took a RMD withdrawal you might have answered the RMD question wrong.
