Go back and double check every single line. This happened to me the past couple of days after getting my first son’s EFC that was double from last year. There wasn’t much difference in our earnings, savings and investments. We are also a family of 5 although with slightly higher combined income of less than 100T. Well this year, my daughter started college too! Instead of putting 2 as the number of students attending college for 2020-21 I entered 1. When I made the correction, the EFC reverted back to close to what we have last year. Check that line.