The User provisioning GET API https://developer.atlassian.com/cloud/admin/user-provisioning/rest/api-group-users/#api-scim-directory-directoryid-users-get

searches for users with usernames alone and not with email IDs. It would be better if this API could also fetch details if the username is an email ID as well. In case if username is not the same as the email ID then it would be difficult to co-relate the Atlassian accounts.

Steps:

Run the below API https://developer.atlassian.com/cloud/admin/user-provisioning/rest/api-group-users/#api-scim-directory-directoryid-users-get

If the username assigned by IDP is: p1234@atlassian.com

The above API will fetch the result but sometimes if the user is trying to fetch the users by searching with email ID for ex: p1234_actual@atlas.com then it won't give any results.