pages_messaging permission required when subscribing for Instagram messages (Facebook app)

Question

I'm creating an app that will allow me to manage my Instagram account, following the guide from here

Now I'm at the App Review stage and I have a conundrum:

• theoretically I should not need the pages_messaging permission (the documentation is not mentioning this as required)
• that being said, when I make my call to register a callback for Instagram messages `POST /v11.0/{page-id}/subscribed_apps?fields=messages&access_token={access_token} the call will fail with WWW-Authenticate: OAuth "Facebook Platform" "insufficient_scope" "(#200) To subscribe to the messages field, one of these permissions is needed: pages_messaging" (this call is the same they are making in the documentation)
• so I've added the pages_messaging permission in my review
• now I'm unable to pass review as they keep telling me that I don't need the pages_messaging permission for my use case (managing Instagram messages) - "We determined that your app's use case for the requested permission or feature is invalid or is not needed to support its core functionality."

Hmm.... what am I missing? Any guidance that you can provide?

Answer 1

After further attempts:

• we could not find a technical way for not needing the pages_messaging permission
• Facebook would not approve this permission for our Instagram app - we got no more details than "invalid or is not needed"
• we resorted to actually increasing the scope of our app to also cover Facebook page messages, we re-recorded our demos to showcase interaction with a FB page.
• with the new approach we managed to pass the pages_messaging approval process

It feels like we're doing something wrong - we shouldn't have had to support Facebook messages and go through the lengthy process of changing our app just to showcase FB page interaction. Not if we only wanted Instagram support.

Alas, as of October 2021, this is how we moved things along. Hopefully something will change in the future to make things more clear & transparent in future.