So I have some treasury interest that is state-tax free. On my MD return, I couldnt figure out why the deduction for "Income from U.S. Government obligations" (MD Form 502SU, Line ab) was higher than the sum of the amounts in my 1099-DIVs from my federal return. I looked at the difference, and it's equal to an old amount I had entered in my federal returns. It seems it's adding that old figure (even though it's no longer there) to the new figures, and using the total for the treasury interest deduction.
How do I fix this error? Note: I cannot delete the return and create it again, b/c I've already paid for it. It wont let me delete it.