Hi @eaact! Welcome to the Zoom community, we're happy that you're here 😊
The duplicates could be because the attendees left and rejoined the session or joined via another device. In your webinar attendee report, you should be able to view details about each attendee, such as when they joined, left, and their total time in session. Attendees listed in the Other Attended section typically include dial-in phone attendees and Zoom Room participants. Here's an article with more information on webinar reports: https://support.zoom.us/hc/en-us/articles/201393719-Webinar-reports
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