Hello! My name is Sandy.I'm reviewing your question now. Let's get started!
In this case, you need to reset your Yahoo account password *****
Once you create a new password, only then, you will be able to check your emails on the mobile.
How to reset your Yahoo account password:
Please go to https://edit.yahoo.com/forgotroot, and try to reset your Yahoo email account password ***** following on-screen instructions.
Once you have new password, please configure your Yahoo email account on your T- mobile.
If you have other queries regarding this, please reply back to me the box given below.
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