The "Something's not quite right. Email address already in use" error occurs because another user has already been invited, using the same email address. There are three ways to resolve this issue.
Option 1: Use a different email address to invite the newest user
If the user you are inviting has another email that can be used to accept the invitation, you can invite them under that alternate email address. For instructions on how to invite a new firm user, see Your Team: Manage users or firm employees in QBOA.
If they do not have an alternate email address, you may consider one of the other offered solutions.
Option 2: Reactivate the original user
In the case that you are attempting to invite a user that you may have already invited previously, but who is now inactive, you can reactivate the original user. For instructions on how to reactivate the original user, see Your Team: Manage users or firm employees in QBOA.
Option 3: Edit the existing user's email
If you are attempting to invite a new user, but another user is already using the email address in error, you can edit the active user's email address and then re-attempt to invite the new user. For instructions on how to edit a team member, see Your Team: Manage users or firm employees in QBOA.