Email instead of username

I am using community builder for user registration, and the site uses the email address for login. The username is automatically assigned as the users first and last name, but they do not know this. How can set the login form during checkout to accept the users email address?

Thank you!

This plugin solved the issue. extensions.joomla.org/extensions/access-...authentication/16246

Hi again Tarik,
This is an outstanding requirement from only your site. It's fine that you can solve it by yourself.
Sincerely, Giang