Error while running Learning App Lesson 8

I am on lesson 8 of Learning App. I have no idea what keys I clicked. But I get following errors when I run the app. The app by itself runs fine. However, when I stop the simulator, I get this error. I have no idea what has gone wrong.
Is it something to do with my settings?
Or is it something to do with my code?
The code is almost replication of what Chris showed us during the course.

Thanks.

Were you using breakpoints in your code while debugging?

No, I did not use any breakpoints. I wasn’t running in debug mode. I just ran this program using Simulator.

Are you getting this error continually or was it a once only occurrence?

So far this seems like a continual problem. It looks like after rebooting my Mac, the simulator can successfully stop the app from running if I terminate in Xcode using the white square in the top left, but when I hit the red close button on the simulator, it crashes and gives me that error. I’ve been closing like this for a while but it looks like something went wrong recently to cause this. This is not something that is urgently disrupting my work flow, but would definitely be good to understand how this happened.

There is no need to close the simulator every time you want to stop the App. It will cause Xcode to crash with a SIGTERM error every time simply because the target device (the simulator) has been shut down abnormally.

Stop the App by tapping the Stop button in Xcode or press Command + . in Xcode.

Ok. Thanks Chris for the clarification!