My iCloud mailbox rebuild is disabled
I recently had to re-add my iCloud account to Catalina mail, and it has two problems, one is that it is stuck in "downloading 1 of xxxxxx" and two, the main one, I wanted to rebuild the mailbox but the "Rebuild" menu entry is grayed out so I can't rebuild the iCloud mailbox. I can't phrase the issue correctly, or else no one has had this issue before, because I can't find a solution.
Has anyone had the "Rebuild" menu entry in Catalina mail disabled, and can you tell me why?
MacBook Pro 15″, macOS 10.15