How to constrain a date entry that allows an enumerator to input age between 15 to 24 years?

@lamo, you could do it as outlined in the image shared below:

In the survey tab of your xlsform:

Data entry screen as seen in Enekto: when a date is entered outside a range

Data entry screen as seen in Enekto: when a date is entered within a range

Image 3

Data entry screen as seen in Enekto: when a date is entered outside a range

Reference xlsform:

Constraint Age.xlsx (9.8 KB)