Android app: Hints are not shown for the lingqs of the day

There are no hints in my lingqs of the day flashcards whatever I choose to be on the back and front.
This problem appeared today.

hmm…
Now it work fine again.

OK, if you notice anything else related to the app, just stick it in the other thread here: http://www.lingq.com/learn/en/forum/2/12272/