@Rildwan, you could do it as outlined in the image shred below:
In the survey tab of your XLSForm:
In the choices tab of your XLSForm:
Data entry screen as seen in Enketo:
Reference XLSForm:
Roster Constraint.xlsx (29.8 KB)
@Rildwan, you could do it as outlined in the image shred below:
Roster Constraint.xlsx (29.8 KB)