After working fantastically for six months, something has happened and I need to clear all the settings and try again. It is doing lots of strange things like not being able to be seen by the Synology Assistant. I am aware of the downgrade trick clearing all settings but keeping data, but this needs Synology Assistant. I also must keep the data on the drives as a backup of 11 TB is not in the cards. I can still ssh in without issue.
I apologize if this has been solved before but I have spent a lot of time on the Google and I didn't see a solution.