@caneeraj, you could do it as outlined in the image shared below:
In the survey tab of your xlsform:
Data entry screen as seen in Enketo: when an entry is made that is outside a range
Data entry screen as seen in Enketo: when an entry is made that is inside a range
Data entry screen as seen in Enketo: when an entry is made that is inside a range
Data entry screen as seen in Enketo: when an entry is made that is inside a range
Data entry screen as seen in Enketo: when an entry is made that is outside a range
Reference xlsform:
Regex_Constraint.xlsx (10.0 KB)