Hi @Maryse MONTIGNE 👋 If your contacts’ Name values have already been set to this, unfortunately you’ll need to set this to a different value if you wish to use this. As you explained, the fallback value will only work if the attribute value is null/empty.
A possible workaround here would be to create a custom data attribute to populate users’ names with, and leave empty is the value is “PRENOM” - with the help of your dev team this could be achieved with a script and the use of our REST API (Update a Contact). This could also be collected via the Messenger when a contact reaches out for the first time, you could tag all users that have “PRENOM” as their name value and send them a workflow to amend this value whenever they reach out via the Messenger.
Going forward, to prevent this occurring, I would recommend making the First Name input mandatory on your site during sign up.
You'll find more on contact data editing in this article from our Help Center ⬇️
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