Thanks for the link. It was rather spooky as it took me right into my own Plex account.
I have made three attempts at setting up a Plex server on a Raspberry Pi with mixed success. Each time I tried accessing Plex on my computer, mobile phone, tablet and via Alexa so my list of approved devices was extensive…
I have cleared out all the unwanted devices and I can start again with an almost clean sheet.
Its difficult when starting on some new venture (Raspberry Pi, Linux, OpenMediaVault and Plex) to get some idea of how the land lies. It has been a steep learning curve and without the help of this forum and those for the Pi and OMV I could not have reached the stage I am at.
Many thanks to you all - I’m sure I will be back again in the future.