Following the instructions for adding Facebook Messenger integration to an IBM Watson Assistant (Watson Conversation chatbot) it all goes well until adding the callback url to the webhooks setting in the Facebook app messenger settings. The URL returns a 404 error.
Has anyone seen a fix for this?
I have managed to find a fix for this. Basically although you can create a Watson Assistant service in any region (EU, USA, Asia etc etc) the integrations only work on services created in the USA region. I recreated the service in Dallas (which created a USA based callback URL) and the Facebook app accepted that url with no issues.
Note I have seen this behaviour with IBM Cloud Functions too. Calling cloud functions natively (which are extremely powerful) from Watson Assistant also requires the service to be USA based.