when user with basic permission they click on Record action they got above error ,If same scenario try by myself with administrator permission it's work fine for me , Basic user have appropriate security permission for Record access and actions
Note: If we think it is related to access issue either we get 401 or 403 issues but it get's different one
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Have you added that basic user to application level users group?Check this documentation:https://docs.appian.com/suite/help/25.2/application-settings.html