I noticed there is an existing post for the 'No calendars for this user' message https://clickup.canny.io/bugs/p/no-calendars-for-this-user-while-connecting-to-google-calendar
But that post is from last year and shows as COMPLETE, whereas the issue started happening some days ago.
I had several Google Calendar synchronizations configured and working correctly (one Space per Google Calendar). Suddenly all Google Calendars that received appointments via this synchronization are now EMPTY.
Attempted to delete and re-create one of the synchronizations and this is when I get the 'No calendars for this user' message.
Need to have this working again ASAP.