2 options:
1- in your site_configuration, in LMS Django Admin, check that you have “lms_root_url”:“http://www.domain.com” , and edit the file “lms/templates/emails/activation_email.txt”, change “lms_url” by “lms_root_url”
2- just go and edit the file “lms/templates/emails/activation_email.txt”, change “lms_url” by “LMS_ROOT_URL”
Restart all services, and try again.
That’s how i fixed it.
Regards,