Have you been able to find a pattern with the nature of the duplicate report emails? Are they of a particular type report only or is there a particular time interval in which you receive those reports? Or is it entirely random? That would help in identifying the issue.
Its the same report that I have created in my dashboard scheduled to go out on the 30th of every month. For eg one report is delivered to the recipient on the 7pm and then another of the same one at 10pm. I look at scheduling options and I cannot rectify.
Your scheduled report setup is looking fine to me. I would request you to reach out to clientcare as it would require a deeper look inside your company settings.
Let me know if you find out the root cause of this issue, it would be helpful for other people having the issue as well. Thanks!
If you are a supported user your can reach out directly to them from Help> Customer Care inside analytics
If you are not a supported user you can ask your company supported user to log a ticket or you can give a phone call to the clientcare yourself.