Hi @anandkjain,
Do you have bot filtering turned on in your HubSpot account?
If you do and are still having issues then go ahead and fill out a support ticket. The issue does not originate in HubSpot’s reporting but from recipients inboxes. It is bots (google image cache, security software, etc.) that are actually loading the embedded pixel we use to track email opens. Still, we work to keep your data as clean as possible.
Cheers,
Jake