Entry Wont save

I'm just about done, but there is one issue that I have the information to fix. The issue simply states that the entry cannot equal zero(0). I can fix this based on the information from one of my tax forms however, whenever I try to input the correct value or attempt to leave it blank(because that is an option as well), it doesn't save. I input the value and click continue but the issue doesn't resolve. I'm stuck because of it.