I have an app which allows customers to message companies directly via a Facebook page, then this message will be routed through my app into my front end service.

Currently I have a company who uses an old Facebook page and a new one.

When a customer sends a message into the new Facebook page, the message is correctly routed and there are no issues.

However, when a customer messages the old Facebook page, the message is only sometimes routed and the rest of the messages do not get sent.

Both pages are authenticated in the same way and they are both are authenticated successfully.

How can I find out where Facebook sends these messages? As it does not even hit our proxy logs for the messages that are not routed. And at no point do these messages ever hit out proxy or get routed through our app.

The old page the customer is using is from 2011