Why is line 3, other income, on form 1099-Misc. not flowing to schedule 1?

[itonewbie]

That's because you must have entered that on the 1099-MISC input page, which is accessible from the tiny prints in the top-right corner of SS Benefits, Alimony, Misc. Income.  You should have read the text in the warning box that says the following (emphasis added):

NOTE: This input screen is required for Form 1099-MISC's on which state withholding is present for AZ, CO, CT, DC, GA, HI, IA, IL, IN, KY, MA, ME, MT, NC, ND, NE, NM, NY, OH, OK, PA, SC, VA, WI or WV. Withholding amounts entered in this screen (for federal & all states) are placed in the e-file and carry to the tax return. They should not be duplicated in the withholding input fields provided in the SS benefit/Misc. Inc. screen or the Passthrough K-1's screen. Income amounts and foreign tax paid, however, do not carry to the tax return and must be entered in the respective input screen to which the income or credit applies (i.e. Schedules. C, E, F, or the SS Ben./Misc. Income screen).

What you should do is to enter that on the main screen on the line for Other Income instead.