Most likely, the reason is that the property has been indicated to be a rental income property.
You can see that on the more info screen for real estate, in the section for rental income property.
The property can be entirely rental property, in which case the mortgage is subtracted from the rental income of the property and will not appear separately on the affidavit.
Alternatively, the property can be partially rental and partially personal, as with a vacation home that is rented for part of the year, or a room that is rented in a home that you own.
In this case, by default, 100% of the mortgage is subtracted from the rental income of the property, and the net amount (along with other real estate expenses) is considered as rental income or loss.
But you can change that by changing the percent of payments on the mortgage allocable to the rental activity, as shown in the image above.
You can see the amount of mortgage allocable to the rental a bit further below. The remainder of the mortgage will carry to the affidavit as a personal mortgage expense.
With regard to other expenses, if the home is entirely a rental income property, all those expenses are natural against the rental income. That result is carried to the financial affidavit with rental income.
If the home is partly personal, You enter the expenses allocable to the mortgage on a single line in this section. Those expenses are mentioned against the income, and the net amount flows to the financial affidavit with rental income.
The other expenses, which you itemize in the Real Estate Expenses section, will then carry to the affidavit directly.