Stuck here, what should I do
Hello bainana,
Sorry to hear that you are having an issue. Could you try reimport all your assets?
It is in Top menu > Assets > Reimport All
Also, it might be related to your license. Make sure you are signed in properly and have a license. If not, please sign in by clicking the account dropdown menu on the top right.
The last one is, please check your internet connection.
If you are still having a problem, please leave a comment.