Show clear error message while inviting users directly after Jira site import

Issue Summary

A new user can not be added/invited directly after Jira Site Import. An administrator have to Approve/Reject groups product access in the Admin panel. While inviting the User the error message created on the UI is not clear.

Steps to Reproduce

1. Run a Jira Site import.
2. Once import is completed, create a new user. (Without approving any groups in the Product Access)
   https://admin.atlassian.com/s/<Cloud ID>/users
3. You will get an error in UI. 

Could not add users

 Unable to add user

Expected Results

 The users should get a correct error message on the UI which could lead them to product group access. 

Actual Results

User get different error messages:

 Error One:

(!)Error Two:

Workaround

Users raise a support ticket to Atlassian to fix this error.