Jupyter not working

When I run the code nothing happens.

I have tried running simple scripts like adding two number in another cell and nothing happens.

Any idea what’s wrong or what I am doing that’s wrong? It was working an hour ago.

(This is the Jupyter that goes along with the course and not the one I downloaded to my computer).

Try restarting the kernel, sometimes it stops working without reason
To do that go to Kernel and restart kernel, if you want you can restart it and run all cells, or just restart it and run every cell by yourself

Than worked. Thanks!