showDialog in flutter is not working in release version of iOS - flutter

Question

I am creating an app for iOS using Flutter.
For that Application, I am using dialogue in one screen.
For that dialogue, It is showing a grey layer on dialogue in the
release version of iOS but it is working as expected in the Simulator or debug version
There is a grey layer on dialogue I have added my code to anyone facing the same issue?
need help.
static dynamic customPage(BuildContext context) {
return showDialog(
context: context,
barrierDismissible: false,
builder: (context) {
return CustomDialog(
insetPadding: const EdgeInsets.all(20),
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.all(Radius.circular(8)),
),
child: Container(
child: Stack(
children: [
Positioned(
child: Padding(
padding: const EdgeInsets.all(8.0),
child: Positioned(
right: 0.0,
child: GestureDetector(
onTap: () {
if (Navigator.canPop(context))
Navigator.pop(context, true);
},
child: Container(
color: Colors.transparent,
child: Icon(
Icons.close,
color: Colors.black,
size: 25,
),
),
),
),
),
right: 1.0,
),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Image.asset(
"images/bind_loader.gif",
height: 90.0,
width: 90.0,
),
],
),
Padding(
padding: const EdgeInsets.only(top: 80.0),
child: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
CustomDialougeUtil(),
],
),
),
Padding(
padding: const EdgeInsets.only(
right: 12.0, bottom: 10.0, top: 120),
child: Text(
"Please wait while we are confirming your payment",
style: bindTheme.textTheme.headline3,
textAlign: TextAlign.center,
),
),
],
),
),
);
},
);
}
// this is a Widget that is showDialog
class _CustomDialougeUtilState extends State<CustomDialougeUtil> {
//State full widget that uses normal timer view to display on dialogue
}