The Stats tab in the SND Messenger Experience tool will give you a look at the past 30 days of usage for your Page's Messenger Experience. There are six metrics available to review, defined below.
Topic subscriptions: The total number of subscriptions to topic feeds through your Page's Messenger Experience. Note that individual users can subscribe to multiple topics.
Topic subscribers: The number of individual users who are subscribed to any topic feed.
Total connections: The number of people your Page can send messages to. This metric shows the number of people who have ever sent a message to your Page on Messenger, not including people who have blocked or reported your Page on Messenger. This metric also only includes connections made since October 2016, when data became available.
New conversations: The number of messaging conversations on Facebook Messenger that began with people who had never messaged with your Page before.
Blocked conversations: The number of conversations with the Page that have been blocked.
Reported conversations: The number of conversations from your Page that have been reported by people for reasons such as spam, or containing inappropriate content.