Where do I disable/remove whatever is contacting d1ph3c47yby10w.cloudfront.net

I keep getting emails that my son’s computer is blocked from accessing d1ph3c47yby10w.cloudfront.net

I’ve tried:
Norton Antivirus - no results
Norton System Clean up - no results
SpyBot Malware Scan - no results
Added AdGuard browser extension

I still get this blocked access notification every 10 min.

Win 10

Hi BlueNegative,

Thank you for reaching out to Norton Family forum.

The domain cloudfront.net seems to be a content delivery network provided by Amazon. If you do not wish to see the email notifications for this URL, kindly add the website "cloudfront.net" to the allowed website list in the Norton Family Web Portal/Parent App.

Regards,
Norton Family Team

 BlueNegative:
my son's computer is blocked from accessing d1ph3c47yby10w.cloudfront.net  

URL Analysed: d1ph3c47yby10w.cloudfront.net
Norton Safe Web has analyzed d1ph3c47yby10w.cloud... for safety and security problems.
The Norton rating is a result of our automated analysis system. 
CURRENT CATEGORY Potentially Unwanted Software

https://safeweb.norton.com/report?url=d1ph3c47yby10w.cloudfront.net 

Since, Safe Web Category = Potentially Unwanted Software

Maybe, run Malwarebytes scan on computer.  
Maybe, ask any recently installed programs/browser extensions? 

Malwarebytes offers free second opinion on-demand scanner. 
Malwarebytes Malware Removal Help offers free one-on-one help.
Malwarebytes staff & experts help all.  Malwarebytes subscription is not needed.