Hey, I you might have this error because your package name (app name/ bundle identifier) is different than the one used in the tutorial. If you click on the Scrumdinger at the top left, then go to tagers -> Scrumdinger you will be able to check your bundle identifier. Change it in your prompt.

I honestly don't get why they make it sound like you will build a project following their tuto while actually YOU HAVE TO download some starter project for some sections to make sure you get some pieces of code that they don't show or explain. It is so confusing. Its a shame, when they actually show/explain, it is quite clear and concise.