If you know your username correctly, you can first try resetting your password and then proceed to sign-in. To reset your password, you can refer to the following Yahoo support page: https://help.yahoo.com/kb/yahoo-account/recovering-lost-forgotten-password-sln2047.html?impressions=true
If you do not remember your Yahoo username, you can recover it by selecting "I forgot my Yahoo ID" option on the Yahoo page below and then following the on-screen instructions: https://edit.yahoo.com/forgotroot/
If you are still unable to sign-in to your account, you can refer to the following Yahoo support page for some more options: https://help.yahoo.com/kb/yahoo-account/unable-sign-account-sln2051.html?impressions=true
Answers & Comments
If you know your username correctly, you can first try resetting your password and then proceed to sign-in. To reset your password, you can refer to the following Yahoo support page:
https://help.yahoo.com/kb/yahoo-account/recovering-lost-forgotten-password-sln2047.html?impressions=true
If you do not remember your Yahoo username, you can recover it by selecting "I forgot my Yahoo ID" option on the Yahoo page below and then following the on-screen instructions:
https://edit.yahoo.com/forgotroot/
If you are still unable to sign-in to your account, you can refer to the following Yahoo support page for some more options:
https://help.yahoo.com/kb/yahoo-account/unable-sign-account-sln2051.html?impressions=true
Hope this will help you.
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