On Schedule H, line 10, I checked "Yes" to "Did you pay unemployment contributions to only one state" but it won't let me move forward. Why does it think that's wrong?

Try deleting the Schedule H and re-enter the information, I believe TurboTax is using the prior year entry for this year.  Windows instructions

1. Open or continue your return.
2. Switch to Forms Mode by selecting the Forms icon.
3. From the menu, select the form you want to remove.
4. After the form is generated in the right pane, select the Delete Form button.
5. Follow any onscreen instructions to remove the form or forms.

Mac instructions

1. Open or continue your return.
2. Switch to Forms Mode by selecting the Forms icon.
3. From the menu, select the form you want to remove (if you don't see it, select Open Form at the top).
4. From the Forms menu, select Remove [form name].
5. Follow any onscreen instructions to remove the form or forms.