I can;t really look into issues on your server whilst you have Plex Media Server binary running in two different instances - one as a service or scheduled task and one as a normal logged in user session
If you run it as a service you must not have auto launch on login for the user account that installed Plex Media Server
You can use the PMS As a Service wrapper here PMS as a service - General / Tips, Tricks & How-Tos - Plex Forum - this should automatically disable the auto start for the login - if same user account is used for the service and for installs
When there are two instances of Plex Media Server.exe running and you can see that in Task Manager, what works and what does not work is indeterminate
