Setup successfullly, but users not receiving notifications

Nextcloud Server:
Nextcloud version (eg, 20.0.5): 21
Operating system and version (eg, Ubuntu 20.04): Raspbian GNU/Linux 10 (buster)
Apache or nginx version (eg, Apache 2.4.25): nginx/1.14.2
PHP version (eg, 7.4): v7.4.15

Nginx Reverse Proxy ( on a separate physical server ):

Note, I have not added a location block to the nginx reverse proxy as I'm unsure the correct way to do that. I surmise that may be the issue of why it isn't working.

On the nextcloud server:
I setup the notify_push service successfully. As least according to the setup wizard.

push server seems to be functioning correctly
reverse proxy seems to be setup already
reverse proxy seems to be setup correctly
configuration saved.

I tested the service with sudo service notify_push status and it's active and running so all good there

I then tested with 2 users using Nextcloud Talk. User #1 initiates a conversation with User #2. User #2 does not receive a notification. User #1 mentions User #2 and User #2 does not receive a notification.

I checked the logs within nextcloud and no errors reported.

In your docs, you mention something about Metrics as a way to troubleshoot, but do not provide instructions for how to do that. Perhaps that would help troubleshoot. In addition, what do you suggest in terms of troubleshooting the issue.

Metrics
The push server can expose some basic metrics about the number of connected clients and the traffic flowing through the server by setting the METRICS_PORT environment variable.
Once set the metrics are available in a prometheus compatible format at /metrics on the configured port.

Thank you.

Start by reviewing the separate nginx reverse-proxy configuration and the notify_push service status on the Nextcloud server. Enable METRICS_PORT and inspect the Prometheus-compatible /metrics endpoint while testing a Talk conversation and mention. Done means users receive the expected notifications and the metrics or logs identify a working path.