Unable to Setup Facebook Messenger Integration

[HugoWiff]

I've been trying to setup the Facebook messenger integration. I've followed this guide on the manual up to step 4, but my test accounts messages are not going through to 3CX. They are definitely leaving Facebook as they are no longer appearing in the Meta Business Suite messaging page (checked with my personal FB account and non-tester messages are still going there)

I have the Route to for the Facebook messaging trunk set to my 3cx user for testing. None of the messages are going through or appearing in the chat logs of the old management console.