Thank you for your answer.
'ctrl + shift before clicking on the sync symbol' did not work for my Evernote.
Even when I was Premium user, clicking Evernote Email Support symbol logged me out of my Evernote.
I did not know the reason.
But I knew nowhere else to ask about this problem.
These 2 problems are too tough to solve by myself.
If you have some hint, please let me know.