def handle(self, *args, **options):
        """Call sync_subscriber on Subscribers without customers associated to them."""
        qs = djstripe_settings.get_subscriber_model().objects.filter(
            djstripe_customers__isnull=True
        )
        count = 0
        total = qs.count()
        for subscriber in qs:
            count += 1
            pc = int(round(100 * (float(count) / float(total))))
            print(
                f"[{count}/{total} {pc}%] Syncing {subscriber.email} [{subscriber.pk}]"
            )
            sync_subscriber(subscriber)
Call sync_subscriber on Subscribers without customers associated to them.
djstripe/management/commands/djstripe_sync_customers.py