I’m not familiar with Sabai OS… so not sure if their VPN router approach is somehow impacting your Plex remote access experience.
Generally I prefer setting up my remote access through a port forward. This allows defining a custom public port and to establish a direct link for requests to that port to your PMS.
https://www.sabaitechnology.com/faq-how-to/#port-forwarding
For Plex, the internal port needs to be tcp/32400.
After establishing this on your router, make sure to check and configure Manually specify public port with the public port you forward in your router.
If you run into issues…
Can you check if you can access your router’s public IP and the defined public port from outside your home network (e.g. using a service such as canyouseeme.org). This will help to identify if the issue is with your ISP/router configuration or within your home network/your PMS.
PS: if your PMS is really on version 1.9.7, you might run into some issues that have been fixed. This server version was released back in November 2017… that’s more then 2.5 years old
