Mail always "Downloading" messages from Gmail
My Mac air continues to show "downloading messages" all the time in email when there aren't any messages to download? Once it finishes, it stops. But then the next day, or at some near-future time, it does it all again.
I've seen many discussions on it but cannot find a simple solution. Recently, I turned off the Archive mailbox thinking that would avoid that, but actually it made matters worse. When Archive was visible on the Mac, GMAIL only downloaded a few at a time. Now it appears to load an enormous number. Today it says it is downloading 28,000 messages, but on my GMAIL account, there are only 6,000 or so in the InBox, and "AllMail only shows 49, and Sent shows about 10,000.
(Interestingly, following instructions from another thread, I turned off Archive, and said Move to Trash. After that, the "All Mail" number shrank significantly.)
Honestly, even though I am tech savvy, at this point, I don't have a clue as to what I am supposed to do to have this Imap Gmail account work more normally. Why is it "downloading" 28,000?
Thanks.
MacBook Air 13", macOS 10.12