gmail account is offline in mail

Good Morning! I have an account with gmail for many years, but it has always shown up in my "Mail" on my apple OS. A few days ago, it showed up as "offline", which has happened before. Any other time it has shown off line, I have chosen "take account online", and unless my wifi was down, it came online. Now it will not. Any suggestions? I so want this to work.

Thank you.

Shelley

[Edited by Moderator]