Is your device connected to a network?
Goocus is an online-based learning tool. Basically, you cannot use it when you do not have an Internet connection.
In addition, some carriers place a cap on their customers’ data communication traffic and limit the connection speed on excess traffic.
Please check if you can use other companies’ services such as YouTube. When the connection speed is limited, it is likely that you cannot load YouTube videos and other streaming services.
If you still have troubles with the display of Goocus although you can use other companies’ services, please make an inquiry via the “Contact administrator” function.