This is something that affects many iOS developers and it’s caused by missing device support files for your iOS device, mostly because you updated your phone to a more iOS recent version.
First go to this awesome repo that contains updates Supports files for iOS simulators.
https://github.com/iGhibli/iOS-DeviceSupport
Download the image that you need (the one that popups in the Xcode error).
Then open this directory:
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport
Extract the content of the zip to that folder.
CMD + Q on Xcode to close it (if it’s running).
Restart your Xcode and re-run your app.
That’s all.