A lot of bug
After the app update, it lost the record that I had paid the lifetime membership. I don’t know how to get it back and access back to the class again. After a prolonged learning, the app had lost the progress record of my son. We have to re-start everything from 101. My son immediately lost the interest to learn anymore. Though it was told that we could get it back from the system. But we failed to do it no matter how many times to follow the instruction in doing so. Very disappointed!