The ios app has been built but can not be run.

I have registered react-native-fcm in my app. All is well, pod, google-serve .. etc .. But build Succeed is done, but it ends as soon as the app continues to run. After the splash screen, I read several issues, and I tried lots of searching. I want to know why. Please help me.

No source file, entry point, or test is named in the report. Start by reproducing the iOS launch failure after the splash screen and collecting the runtime or crash output; done means identifying a reproducible cause and verifying a fix.

Written by the indexing model from the issue text.