Facebook Custom Audience sync issues are one of the most common problems with Person-Level Advertising (PLA). In most cases, the issue is caused by an expired or revoked OAuth token, which means the connection between Visual Visitor and your Facebook Ads account needs to be reconnected.
You may be experiencing a sync issue if:
If you have access to multiple Facebook Business Manager accounts or personal ad accounts, make sure you are authenticating with the correct Facebook account that has access to the intended ad account. Connecting the wrong account is a very common issue.
If your Facebook Ads account is restricted from using Custom Audiences, you may need to accept Facebook's Custom Audience Terms of Service.
In Facebook Ads Manager, go to:
Business Settings > Data Sources > Custom Audiences
and accept the required terms.

If Two-Factor Authentication (2FA) is enabled on your Facebook account, you must complete the 2FA verification step during the connection process. If the verification is not completed, the OAuth connection may fail silently.
