How Do I Delete Nonexistent Notifications?

For desktop: When you have a new notification, select the 'New Updates' bubble that appears in the upper right of your browser window. 


A notifications pop-up will appear. Select 'X' next to the notification you’d like to delete. 

For mobile: At the top of the screen, tap 'Updates', and you'll be taken to another window, then tap the 'X' next to the notification you want to clear. See screenshots below.