If your notification (Reminder) is not working, notifications for Wants and Needs may be turned off on your device.
1. Go to your device’s Settings menu.
2. Tap Notifications.
3. Scroll down until you find Wants and Needs.
4. Tap Wants and Needs.
5. Make sure Allow Notifications is turned on.
Note: From this menu you can also adjust some of the settings for your Wants and Needs notifications.
Additional links you may find helpful:
Apple Support: Understanding notifications on iPhone, iPad, and iPod Touch
Wants and Needs: How to Set a Notification (Reminder)