This is example of icloud problem of running out of space.
You can turn off the iCloud notifications completely by doing the following steps:
- Go to Start menu and open Settings
- Click System
- Click Notifications & Actions
- Scroll down to “Show notifications from these apps
- Click on iCloud and it will give you three options. You can either turn notifications off completely, turn off “show notification banners” and turn off the sound when the notification arrives.
Hope this helps!