Difficulty Enabling Remote Access with Plex Running on Seagate Personal Cloud



I'm hoping the geniuses on this forum can help with a nagging problem. My plex is currently set up with identical libraries (I add the same files to both) connected to a 4TB external hard drive and a 5TB seagate personal cloud (SRN21C). I use the personal cloud when I am on my home network and I use the 4TB external when I am away from home, but it requires having my laptop and plugging in the hard drive in order for Plex to be able to find the port. What I would like to do remove the need for the 4TB external hard drive and enable remote access to the seagate personal cloud, with my assumption being that after remote access is configured I could access that library outside of my home network without needing the 4TB external hard drive. I have the "Your server is signed in to Plex, but is not reachable from outside your network," message and have followed the troubleshooting information to allow access through my home router (manually specifying the port), but that didn't work. Is anyone aware of specific instructions that would allow me to enable remote access to the Seagate Personal Cloud or has anyone had success with what I'm trying to do and can walk me through it?