If you don't have an IceTV account you can try IceTV by creating a free IceTV subscription to use with your Plex DVR at https://www.icetv.com.au/plex. This will guide you through configuring Plex DVR to use IceTV as its TV guide data source.
If you already have an IceTV subscription go to https://www.icetv.com.au/plex and log in. Then follow the steps to configure the Plex DVR to use IceTV as its TV guide data source.
If you have any questions or issues please contact support