Here are the steps to change Yahoo mail password?
Your Yahoo password gives you access to every Yahoo service you use. If you've forgotten your password, you can reset it to get back into your Yahoo account. It's also a good idea to update your password regularly and to make sure it's unique from other passwords you use.
Change your password
From a desktop or mobile web browser:
Sign in to the Yahoo Account security page.
Click Change password.
Enter a new password.
Click Continue.
From most Yahoo mobile apps:
Tap the Menu icon Image of the side menu icon..
If using the Yahoo Mail app, tap Manage Accounts.
Tap Account info.
Tap Security settings.
Enter your security code.
Tap Change password.
Tap I would rather change my password.
Enter the new password and its confirmation and tap Continue.
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