Constraint on date of birth

[Kal_Lam]

Welcome to the community @rimaoulleik! Would you mind having a look at the post discussed previously (it should solve your issue):

How to limit the Date of birth to be at least 18 year ago

Maybe you could try this out as outlined in the image below: In the survey tab of your xlsform: [Image 1] Data entry screen as seen in Enketo: When a wrong entry is made [Image 2] Data entry screen as seen in Enketo: When a correct entry is made [Image 3] Reference xlsform: Calculate Age.xlsx (9.7 KB)