This error is exactly as it reads, the news client is not getting the expected credentials. Here are a few things to try.

• If you have recently changed your password on the website, please ensure you have updated it in your newsreader as well. Some newsreaders will not update it automatically.
• Ensure you are not using your email in a field that asks for your username.
• If you are copying and pasting your credentials, please ensure that you are not copying and pasting spaces along with that information.
• Ensure that your password manager has the updated credentials after a password reset.