Matlab2019a stucks in "Initializing" Simulink and stucks in the simplest calculation in command window

Hi,

I just installed Matlab2019a academic. Everything looks good with the installation and the start of it. But it takes a very long time and seems no end to initrialize Simulink. Besides, it cannot do the calculation when I input "1+1" in the command window. I also tried other buttons on the menu, for example, the Adds-On, and they are all not response.

At first, I think this issue may be caused by "license". But the issue still exists even though I opened Matlab under the root directory "$MATLAB/bin/win64/matlab.exe". Could you please help me with this issue?

Thanks!