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If this is the case, please check if any of your Atlassian applications has a default access group configured. Please follow this Atlassian documentation: https://confluence.atlassian.com/adminjiraserver/manage-group-access-to-applications-938847042.html or You may follow this Atlassian Community post: https://community.atlassian.com/t5/Jira-questions/How-do-I-edit-the-Default-access-group-in-JIRA/qaq-p/1232781
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