
RaviS.80313 (Customer) asked a question.
Past one week while login to Okta first time couple of new joiners facing the issues. Part of their Active Directory Profiles those set of users having multiple groups. After ran the import task only few groups are assigned to user Okta Profile. Since Okta logs was not shown the reason behind this error and we are facing the challenge to identify the root cause. To mitigate this issue time being we are deactivate the user Okta account and request them to login again.

Thanks for your question.. this could be due to any number of potential reasons, but it would be helpful for you to ensure that the user is properly AD-mastered, you correctly have what I assume to be Delegated Authentication, and then finally for the groups, please ensure that under your AD integration you select "Provisioning > Integration" and ensure that the appropriate OUs are selected from which you would like to draw users & groups from.
Please see below links for examples of what could be causing your issue. Please ensure that there are no duplicates, no time based login restrictions, the account is not expired/disabled, it is properly mastered, the password itself is not expired, etc. Providing a few more details would be helpful.. Deactivating the Okta account would not allow these users to login, so it is important for us to understand your user creation flow as well. Thanks!
https://support.okta.com/help/s/article/AD-mastered-users-getting-error-NOT-SPECIFIED-and-failureFound-more-than-one-User-ambiguous-login-attempt-in-system-logs-upon-login-to-Okta-with-their-AD-credentials?language=en_US
https://support.okta.com/help/s/article/Users-unable-to-login-into-Okta-and-getting-NOT-SPECIFIED-and-ErrorCode-1328-in-System-logs?language=en_US