I tried disabling it entirely for all sites, restarted Safari.. and it still nags meThere's a chance that your ad blocker is not recognizing the your response to the button.
I also found a tutorial on how to disable notifications and notification requests on Safari, give it a try and if that doesn't work, let me know: http://www.iphonehacks.com/2016/11/...e-push-notification-popups-safari-chrome.html