Support

There are two emails which can be sent in this case.

One email uses the "Admin Tools: Failed administrator login" mail template which does include the username and IP address. This is sent on all failed admin logins, assuming you have set up an email address in the "Email this address on failed administrator login" option.

The other email uses the "Admin Tools: Automatic IP blocking" mail template. This cannot include the username because that piece of information is not communicated to the part of the code sending this email. That code only gets the block reason without any additional information.

The username will, however, be visible in the Blocked Requests Log as long as you have enabled the Log usernames option, see https://www.akeeba.com/documentation/admin-tools-joomla/waf-configure-joomla-hardening.html. I assume you want to correlate blocked IPs and usernames. That's what you should be using, if I understand your use case correctly.