If you experience a red box around an email, this means the email is being used on another school's LiveSchool account– either a trial account or at another school. It might also be that the user you're trying to add is already in the account.
The teacher/admin can edit the email address they use to log into their other LiveSchool account so their primary email can be used with your school's account. If the teacher is a Clever user, they will have to wait until their school of record is updated in your SIS.
If there are school staff that work with LiveSchool at multiple schools, to create separate logins for each school just add "+SchoolName" (or any other text) to the end of their email and before the "@" sign and they'll still receive all emails at their primary email address.
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