Ionic app is not working on IOS 10 and below

#1

Hi, We have upgraded to mojave and XCODE 10.2
And building our application using below command

ionic cordova build ios – --buildFlag="-UseModernBuildSystem=0"

App works well on the IOS 11 and 12
But it is not going past the splash screen in the ios 10 & 9

APP stuck on splash screen when using --prod (IOS 10 or lower ONLY)