I am setting up for my next session and all my compendiums are gone. In addition to that I tried to create them again and am unable to import with D&D Beyond Importer or create a compendium manually within Foundry. Any suggestions?
Hey there 
Is it possible that this is a v10 issue where they are shared compendium no longer meets requirements for validation? Can you please check through this article, and if it is related, this tool can help you out.
You should also check the Bazaar to make sure your modules are updated!
Otherwise, you might need to check in your dev tools console (F12) and refresh, then try to access/create the compendiums again to see what is going wrong. You can also post a screenshot of any errors you see there to our #forge-support channel in the Discord server, someone’s usually around to help 