How to handle overlayEntry as a AnimatedContainer child in flutter?

i am trying to make Overlayentryas AnimatedContainer child .. so there is animation from top secren to down ,,

it is work as expected but the problem is when i put my Overlya as AnimatedContainer child there is no animation anymore ALSO there is yellow line under my text ..

here is my code

  @override
  void initState() {
    WidgetsBinding.instance!.addPostFrameCallback((_) =>receiveCall())
  }


OverlayEntry? entry ;
receiveCall(){
 entry = OverlayEntry(
          builder: (context) =>
    
           SafeArea(
                child:  Align(
                alignment: Alignment.topCenter,
                 child: AnimatedContainer(
                 duration: const Duration(milliseconds: 300),
                 alignment: Alignment.center,
                 height: call? 200:0,
                 //  width: 50,
                  color: Colors.yellow,
                  child: const Text('Call'), // here i am getting yellow line under my text
                    ),
                  ),
                ),
          );
          Overlay.of( context)!.insert(entry!);
}
  

my issues 1- yellow line under my text 2- there is no animation anymore