Any malfunction with Yahoo's products may cause your account to be suspended. Yahoo is very strict about maintaining the quality of its products and services. The Sign-in Helper can be used immediately to regain access to your Yahoo account if it has been locked temporarily. To unlock Yahoo email password, use the Yahoo Help Forum Page. Now, you must click on the 'Account Locked' message. Now click on 'Sign-in Helper' and enter your Yahoo Mail address or phone number. Now, you will receive an 'Account Key' through your recovery mail/phone or be asked for security questions. Follow the on-screen steps, and you will be able to unlock your locked Yahoo Account immediately.

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