An email campaign from my Workflow has been sent to the same contact twice.

As it is shown in the screenshot, Generic Email 1 is sent twice, first one is 'Opened' and the other one 'Sent'.

Did Zoho detect that it is the same person, so the mail had been intercepted by Zoho before it became delivered? Or is it just a coincidence that the email was not able to reach the inbox for whatever reason? I am not sure if other leads have received the same campaigns twice. I would like to make sure that there is no chance that this actually happens.

If it is relevant, I have changed the Sync name in Sync Services, which syncs the data between the mailing list associated with that Workflow in Campaigns and the CRM. There has also been multiple new Versions within the same Workflow since the first email had been sent out.

Thank you in advance.