The first thing to check in those cases where leads aren't being successfully created via Facebook is to make sure the Facebook settings are correctly set up. For this, you can follow the steps below:
Revoke access to Facebook from the Lead management settings page by clicking the ⋮ button next to the existing Facebook connection.
Connect Facebook to the corresponding account once again.
Make sure it's connected to the business account you are creating the forms with.
While in business settings, make sure Momence Leads is a connected app by navigating to Connected Apps under Integrations.
Ensure the Leads access is set up properly by navigating to Leads Access under Integrations
In the CRM tab of the Lead access window, you must have Momence Leads as a connected CRM
From the previous screen, click on the three horizontal bars and select Meta Business Suite.
Create the form and make sure it's set to "Open" in the settings.
Test the form with a randomized email such as [email protected].
In case you need to understand what the issue is when creating a Lead via Facebook, you can also navigate to the Facebook integration history logs. These can be accessed via the Lead management settings page, by clicking on the ⋮ Facebook & Instagram lead ads integration. This will give you context on whether leads are being successfully created or not.