Others are having this issue as well. Some were able to get their feed back by turning off their location.
I turned off Location Services, Stories to Read did reappear. But that costs you location in Google Now, apps etc.
You may have to turn it off and on depending on what you want. This was an actual bug issue a few months ago.
Your cards should work this way:
Google Cards is an easy way to be notified about upcoming events on your device. If Google Now not showing cards, or you need to disable / enable some cards, do as follows:
1. Open Google Search to see your cards
2. Press Menu Button, and tap Settings
3. First make sure "Google Now" is enabled and tap on it to manage cards (Tap the text)
4. Now you should see list of all cards and a toggle button to turn it off or on
5. Scroll through the items enable / disable cards
Another fix that has worked for some iphones:
Go into settings, now cards, and delete card preferences, pop up says this will delete across all you devices, hit ok. Now cards gone from phone. Back to google search and set up again. All cards back.