I'm using the lead ads tracking add-on for Facebook with the Facebook Lead Gen form. It works really great to bring contacts over from the Facebook form into a Hubspot list.
Recently, the add-on got disconnected from our Facebook and we lost 700 contacts coming over into our list and workflow. I was able to get them imported seperately. Hubspot wasn't able to tell me the exact cause of the issue yet.
It would be awesome, if Hubspot could give an alert on our account if one of our add-ons is disconnected.