I have been using 4 email accounts with TB for years now with no problems - 2 use IMAP gmail accounts and two POP mail accounts. In the last week, when I open TB (on a mac OS10.15.7) I am asked to enter the password for these two accounts. I have not changed the passwords for these two accounts anywhere else so I don't know why TB suddenly wants me to enter them. No matter what password I enter here, I am told the login failed and am asked to enter a new password. I enter a new password and go back to being asked for passwords again.

What password is TB looking for? Where is it stored so that I can look for it? When I go to Settings/Privacy and security/Saved passwords only passwords for the two gmail accounts are shown. Where can I find the passwords for the POP Mail Server and how do I reset them?