I can't delete the extra entry on Line 1b(2).

[lwilliamsziler]

I only lived in Maryland 01/01/2016 - 12/31/16 but there's an extra entry. Getting blocked from progress because it says I have 366 or more days entered. How do I get the second line deleted?

[MikeA]

You visited the Sales Tax Deduction area in in the Federal return and the entries need review.  Visit "Deductions and Credits" -> "Estimates and Other Taxes Paid" -> "Sales Tax"

Most likely all of the entries total to more than 366 days (leap year) lived in a state or states.  Just double check the date ranges and ensure there is nothing overlapping.