Posts under category Facebook Instagram Platform

All accounts connected to our App are missing stories impressions metric from Instagram webhook. I attach some responses i get from all accounts:
{"value": {"media_id": "mediaId", "impressions": 0, "reach": 20140, "taps_forward": 20460, "taps_back": 1559, "exits": 4290, "replies": 0}, "field": "story_insights"} {"value": {"media_id": "mediaId", "impressions": 0, "reach": 381, "taps_forward": 300, "taps_back": 11, "exits": 53, "replies": 0}, "field": "story_insights"} {"value": {"media_id": "mediaId", "impressions": 0, "reach": 43, "taps_forward": 38, "taps_back": 5, "exits": 2, "replies": 0}, "field": "story_insights"}
What could be happening? Regards, David.

Hello everyone, I'm trying to simply add a tester for my Instagram account unfortunantly it's not letting me it's returning a weird error Form can't be saved Please verify all information is entered correctly and try again|
would you please help me figure this out ?