To do that, see how to clear your cookies in Chrome, Firefox, Microsoft Edge or Safari. If your sign-in isn't working, but you're not seeing an error message - the page just reloads after you enter your username and password - you might need to clear your browser's cookies. It's possible you changed the password at some point in the past and didn't record the change.

You can also try to reset your password using the Forgot password? link.

If you're using your browser's autofill tool, disable it and enter the username and password manually.

If you are unable to find the sign out or log out option on Yahoo email app, go to Settings, head over to Mail, Contacts, Calendars and then turn off mail sync option.

Here, you will see the option to sign out. Click on it and go to Manage Accounts option. If or when you re-enable the account, the Mail app will download any messages on the server that haven. Tap on that icon and you will see your account name. That specific mail account is now disabled and the Mail app won’t be able to use it any further. Select the email account you want to log out from on the left. If the problem persists, try logging in on a different device or use a different web browser. Click the Mail > Accounts option at the top.Double-check your spelling, making sure you're using the right capitalization and not confusing similar characters, such as I, L, and 1. This usually means you've made some sort of typo when entering your credentials.

You might also see an invalid ID or password error when trying to sign in. Use the Forgot username? or Forgot password links to sign in if you can’t successfully enter your credentials.

How to sign out of yahoo mail app