Flutter App build

I have an already built flutter app but i have made some changes and i can't deploy it on apple store because it's rejected. Here is the reason "We discovered one or more bugs in your app when reviewed on iPhone and iPad running iOS 12.1.4 on Wi-Fi. Specifically, the app fails to fully load. The app only shows a single dot on the screen, and nothing else. Nothing happens when we tap the dot. The app exhibits the same behavior on multiple devices. Next Steps To resolve this issue, please run your app on a device to identify any issues, then revise and resubmit your app for review. If we misunderstood the intended behavior of your app, please reply to this message in Resolution Center to provide information on how these features were intended to work. For new apps, uninstall all previous versions of your app from a device, then install and follow the steps to reproduce the issue. For updates, install the new version as an update to the previous version, then follow the steps to reproduce the issue. " that means something wrong on my developer build so i need someone to build it for me thanks