How to use the ios app as a remote control for the Windows 10 Plex app or Webserver?.

I want to control my Windows Plex App or the Plex Server remotly from my ios Plex app.
In the IOS app my Windows Plex app is listed as a player, but when I try to playback nothing happens and the option to choose the Windows app dissapears untill I restarts it.

Any idea on how to get this working?

Sometimes I can connect to the Windows App or the Server and stream the media, but it rarly works and bugs out fast.
Any idea on how to make this more stable?.