Hi @stephenw10
Thanks your post pointed me to where to restart the monitoring service.
My google searches were failing me.. Everything I found said that restarting it was some where under the System -> Advanced Settings area. But I couldn't find it.
However it's under that Status -> Monitoring -> Settings ->"Display Advanced" button..
Sigh. Now I know the term to search for it's easy..
After disabling and enabling Graphing again it's fixed!
Cheers
Richard