What exactly are "Nondeductuble expenses from prior years"?

TT Home and Business 2018 is asking me to enter any of these that I might have, but I can find no explanation. The first two blank fields are labeled "Operating Expenses" and "Depreciation Expenses." This is for a mixed-use rental property.

I'm moving from years of my accountant doing my taxes to my first time with TT. On my 2017 return's Schedule E, she showed no profit or gain by, it appears, not taking the full depreciation expense for the year. To me that looks like a loss that I'm not going to be able to "keep" going forward. And this approach of hers appears to go back for years.

1) Is it likely that this loss being kept track of elsewhere?

2) Would  these fields be a good place to try to do some "catch-up" on my prior year loss tracking, or are they meant for something else. If so, what?

Thanks.

Dave