Code won't run in playground

I’ve replicated the code used in Lesson 9 and it won’t run. The play button shows but not the square. When I press the run button on the side (in the blue circle) nothing happens. And when I press the run button at the bottom nothing happens. There is just the play button. Never the square. How can I fix this? Thanks

What dows it say at the top when its running? It might say “indexing” or something… This means its preparing a lot of things in order to make playground work fast in thr future… It might be organizing stuff or it might even be downloading packages… Best to wait for it until it finishes… Dont worry once its done it will run fast

Hi. I don’t know what the message at the top was while the run was not working. But, I’ve come back to it after a few days and it’s now running.
Not sure what the issue was , but it seems to have resolved itself.
Thanks.