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Allow or block notifications from all sites
On your computer, open Chrome.
At the top right, click More 
Settings.
Under "Privacy and security," click Site settings.
Click Notifications.
Choose to block or allow notifications:
Block a site: Next to "Block," click Add. Enter the site and click Add.
Allow a site: Next to "Allow," click Add. Enter the site and click Add.
This appears the same for allowing or blocking a website.
Ran into an issue where a user had McAffee advertisments popping up through notifications. This had resolved the issue. Another possible solution would to reset chrome.