Text and meaning of the error
Such an error may occur when using the Yahoo mail service.
The error message can look like this:
Invalid login: 535 5.7.0 (#AUTH005) Too many bad auth attempts.
This message means that you are trying to use your personal email password in Studio Pro. Yahoo does not allow using personal passwords in third-party applications (in this case, Studio Pro).
To avoid this error, generate an app password. You can learn how to do it in this instruction. After the password is created, you need to update the Yahoo credentials using the generated app password.