Facebook Graph API not Returning Leads for Specific Ad but Visible in Ads Manager

I’m facing an issue where the Facebook Graph API is not returning lead data for a specific ad, even though the leads are visible in the Ads Manager.

Here’s what I’ve done: I’m using the following endpoint to retrieve the leads: GET /{ad_id}/leads?fields=id,created_time,field_data&limit=1000

The leads for other ads are returned correctly, but for one particular ad ("ad1 - Copy"), no leads are returned, even though I can clearly see them in the Facebook Ads Manager (65 leads in total). I’ve made sure that my access token has the required permissions: leads_retrieval ads_read ads_management pages_manage_ads I’ve also tried adding parameters like date_preset=maximum, but this doesn't help with retrieving the missing leads. I've checked Stack Overflow and the Facebook Developer forums, but I haven't found a solution specific to this issue. Has anyone encountered a similar issue, and is there a known fix or workaround for this discrepancy between the Ads Manager and the API? Any help or guidance would be greatly appreciated!

Environment: API version: v20.0 Access token permissions: leads_retrieval, ads_read, ads_management What I’ve Tried: Refreshing the token and regenerating it with proper permissions. Adding various query parameters (like limit and date_preset). Expected Behavior: The API should return all leads for "ad1 - Copy" just like it does for other ads.