If your course progress is missing：
a) Please ensure that you sign into the account correctly because there will be 3 different accounts if you sign into the account via email/password, Google, and Facebook.
b) If the account has no problem, please click”ME >> Backup“.
If the review data is missing and the course progress is normal:
Please click “Me >> profile photo>> setting button on the right-up corner>>recover review progress” .
If you have tried all the above methods and the problem still persists, please try reinstalling the app as a final resort. If the issue continues to exist, please feel free to contact customer service at nihao@chineseskill.com.