Hi Jessie,
Hope you are well.
When you run the report, please go to Data > change report data and check the date range set up within the 'Selection Criteria'. If it is set up as 'Previous two quarters' it will display the data for last two quarters which is 'Apr-June/July-Sept'. If you want to display the current data as well, I would suggest you to change the date range as 'All' or use custom date range and select the date range.

If not, then I would suggest you to please confirm the report name that you are running and the event's name for which the email data is not showing and we'll check it further for you.
You can also refer to the following article for your reference :
Your Guide to Running Reports in Cvent == LINK : : https://support.cvent.com/s/communityarticle/Your-Guide-to-Running-Reports-in-Cvent?is_article=true&lang=en_US&searchFor=running%20a%20report&page=1
I hope this helps. Please let us know if you have any further questions.
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Raashi Semwal Khati
Senior Quality Analyst
Cvent
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