If your account is already linked to Login.gov or any other 2 factor provider, you will not need this password to log in.
How to Reset an Expired Password
Login to Grants.gov using your username and password. If your password is expired, you will be directed to the Reset Password page.
Enter your old password and a new password based on the requirements listed on the Reset Password page.
Click the Submit button. You will receive an email notification of your password reset.