BUT the most important thing is When in this case you click on Reset Password, when you are forgot your password, the Retrieve password Pop-up coming:

With Following Notification Text Block and a field to fill by User name (Email Address):

If you forgot your password an email with a password reset link will be sent to your registered address. Click on the link in that email and you will be taken to a page where you can then create a new password.

I type host Email and also I try by 2 other Email and Old User name but Just following text coming!!!!:

Please Enter Your User Name

I Enter My User name (host) and also try (host Email) also I try bu other user names... Never success to get Email to reset password. always show me: Please Enter Your User Name

Any Suggestion to fix it? What is problem?

I am having the same issue. Can you give me more details on how to correct the issue.

I selected user email as username.

On the password reset it asks me to enter my username but no field is available.

I have checked the database and the user name is the email address.

This is going to cause a lot of issues for the users.