Hi @Zhao_Nan ,
Does this issue persist all the time?
What is your version of Teams for Linux?
I did a test in my environment but it seems no issue here. When you sign in your account, it will ask you if you need to stay sign in next time. If you select yes, you can sign in without password next time.
I also found if you select no option but if you enable “Auto-Start application” in Teams client settings, you can also stay sign in status. Maybe you can try to check if it works for you.
If the above is no helpful for you. We recommend you try to clear your client cache file and restart it to see if it can be fixed.
rm -r ~/.config/Microsoft/Microsoft\ Teams\ -\ Insiders
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