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- Facebook Messenger App Invalid Scope - permission: pages_messaging_subscriptions 3 answers
I had a submitted and approved Facebook messenger bot working. But I just got a developer update just now saying "Your Webhooks subscription for callback URL https://BOTNAME.herokuapp.com/ has not been accepting updates for at least 16 minutes. Please verify that your callback server is functioning."
I do see that my callback server and application is working on Heroku.
This problem usually gets solved if I generate a new page access token and restart the web application with this new page access token in it. But this time I'm unable to generate an access token either.
I tried generating a new page access token from my Developer account page for the specific page on which the app is running, but the error now says "Invalid Scopes: pages_messaging_subscriptions. This message is only shown to developers. Users of your app will ignore these permissions if present." There is no Documentation on this. Any suggestions?