Hello, 

I don’t have any conversion on facebook ads, even though the IDFA are sent to Facebook on Revenue Cat and the traffic only comes from Facebook ads.  

I have read the docs but could not find a proper full example. 

Here is what I have done (swift).

I have tested where to call FBSDKCoreKit.AppEvents.activateApp() (before or after ATT request)
 

Option 1:

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterDelegate {

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: pUIApplication.LaunchOptionsKey: Any]?) -> Bool {


        FBSDKCoreKit.Settings.isAutoLogAppEventsEnabled = false
        FBSDKCoreKit.AppEvents.activateApp()

        Purchases.automaticAppleSearchAdsAttributionCollection = true
        Purchases.configure(withAPIKey: "XXXXXXXX")
        Purchases.shared.collectDeviceIdentifiers()
        Purchases.shared.setFBAnonymousID(FBSDKCoreKit.AppEvents.anonymousID)

        if #available(iOS 14.5, *) {
             ATTrackingManager.requestTrackingAuthorization { status in
               switch status {
                   case .authorized:
                      Purchases.shared.collectDeviceIdentifiers()
                      FBSDKCoreKit.Settings.setAdvertiserTrackingEnabled(true)
                      FBSDKCoreKit.Settings.isAdvertiserIDCollectionEnabled = true
                   default:
                       FBSDKCoreKit.Settings.setAdvertiserTrackingEnabled(false)
                       FBSDKCoreKit.Settings.isAdvertiserIDCollectionEnabled = false
                }
             }

          } else {
               Purchases.shared.collectDeviceIdentifiers()
               FBSDKCoreKit.Settings.setAdvertiserTrackingEnabled(true)
               FBSDKCoreKit.Settings.isAdvertiserIDCollectionEnabled = true;
        }
    }
}

Option 2:

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterDelegate {

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: OUIApplication.LaunchOptionsKey: Any]?) -> Bool {

        FBSDKCoreKit.Settings.isAutoLogAppEventsEnabled = false
        Purchases.automaticAppleSearchAdsAttributionCollection = true
        Purchases.configure(withAPIKey: "XXXXXXXX")
        Purchases.shared.collectDeviceIdentifiers()
        Purchases.shared.setFBAnonymousID(FBSDKCoreKit.AppEvents.anonymousID)

        if #available(iOS 14.5, *) {
             ATTrackingManager.requestTrackingAuthorization { status in
               switch status {
                   case .authorized:
                      Purchases.shared.collectDeviceIdentifiers()
                      FBSDKCoreKit.Settings.setAdvertiserTrackingEnabled(true)
                      FBSDKCoreKit.Settings.isAdvertiserIDCollectionEnabled = true;
                      DispatchQueue.main.async {
                           FBSDKCoreKit.AppEvents.activateApp()
                      }
                   default:
                       FBSDKCoreKit.Settings.setAdvertiserTrackingEnabled(false)
                       FBSDKCoreKit.Settings.isAdvertiserIDCollectionEnabled = false;
                       DispatchQueue.main.async {
                          FBSDKCoreKit.AppEvents.activateApp()
                       }
                }
             }

          } else {
               Purchases.shared.collectDeviceIdentifiers()
               FBSDKCoreKit.Settings.setAdvertiserTrackingEnabled(true)
               FBSDKCoreKit.Settings.isAdvertiserIDCollectionEnabled = true;
               FBSDKCoreKit.AppEvents.activateApp()
        }
    }
}

In either case I have some IDFA collected and sent to Facebook but I cannot see any conversion events. 

Thanks for your help,