Hello @Marina ,
I definitely haven't reached the end of the Spanish course yet as I'm on level 9 but something might have gotten mixed up in the system which caused the problem. I'm thinking that I possibly overloaded it somehow seeing as I've been learning very intensively for the past three days.
It is working fine in the browser and the application from Apple Store, the problem seemed to only be with the one from Play Store (I had used the same device to practice at lingvist.com without any troubles).
It was fine today.