Does your event display the registration list page on your registration site before or after registration? Is your event a public registration site that anyone can find via a search engine?
I personally have only had to deal with a similar situation but relating to hotel blocks for the event not from Cvent. In the past, we would send out a notification to all invitees and registrants informing them of spam messaging and highlighted what they should look out for as a valid email from the event.
On another note, I would recommend that you report the email address and domain to be blacklisted. Once this happens, it is very hard to get off the list. It is not fool proof as with email spoofing, and other techniques, there are ways to get around systems that are meant to protect our constituents.
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Lindsay Buchanan
OpEx Technology Administrator
Gilead Sciences, Inc.United States
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