This is Jaehwi from Koreanclass101.com
Thank you for posting!
Our tech team has looked into it, and apparently there is only an issue with the way the top Deck view is displaying (where it shows 0%). If you go inside a deck (Edit Deck), you will see your real progress. We are working on a fix for where it is showing 0%. We apologize for the inconvenience.
Let us bring you the answer back as soon as the issue gets fixed.
- Jaehwi / Koreanclass101.com