Prevent duplicate entry on a form

Bonjour à tous,
S’il vous plaît comment empêcher la saisie des doublons sur mon formulaire Kobo ??
Par exemple empêcher qu’une personne s’inscrive plusieurs fois sur un même formulaire.
Merci pour votre aide.

@Adnan, maybe you could dynamically link the project to itself to see if the id has been entered previously (this will let you know if a submission with the same id is already entered into the project). This, however, does not restrict you from entering the same response anyway. However, the downside of this approach is that you will get an error message when trying to edit your submission. We have thus not updated our support article for the dynamic data attachment. We will update it once we overcome this known issue.