In my android flutter application after entering in the text box for typing phone number, the phone text box is not moving to the top. It is hiding by the numbers. So, How to resolve this issue? Background image bg.png size is 789X1665 . So, Need to resize the bg image or need to add some code changes? Please help anyone to resolve this issue.

```
  return Scaffold(
  resizeToAvoidBottomInset : false,

  body: Container(
    height: MediaQuery.of(context).size.height,
    width: MediaQuery.of(context).size.width,
    decoration: BoxDecoration(
        image : DecorationImage(
            image: AssetImage('images/bg.png'),
            fit: BoxFit.contain
        )
    ),
    child: SingleChildScrollView(
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [

          SizedBox(height: 500,),

          Container(
            margin:EdgeInsets.only(top: 10),
            child: const Center(
              child: Text(
                "Phone (OTP) Authentication",
                style:TextStyle(fontWeight: FontWeight.bold,fontSize: 20) ,
              ),
            ),
          ),

          SizedBox(height: 10,),

          SizedBox(
            width: 400,
            height: 50,
            child: CountryCodePicker(
              onChanged: (country){
                setState(() {
                  dialCodeDigits = country.dialCode!;
                });
              },
              initialSelection: "IN",
              showCountryOnly: false,
              showOnlyCountryWhenClosed: false,
              favorite: ["+1", "US", "+91", "IND"],
              hideSearch: true,
              showDropDownButton: false,
              enabled: false,
            ),
          ),

          Container(
            margin: EdgeInsets.only(top: 10,right: 10,left: 10),
            child: TextField(
              decoration: InputDecoration(
                  hintText: "Phone Number",
                  prefix: Padding(
                    padding: EdgeInsets.all(4),
                    child: Text(dialCodeDigits!),
                  )
              ),
              maxLength: 12,
              keyboardType: TextInputType.number,
              controller: _controller,
            ),
          ),

          Container(
            margin: EdgeInsets.all(15),
            width: double.infinity,
            child: ElevatedButton(
              onPressed: (){
                Navigator.of(context).push(MaterialPageRoute(builder: (c) => OTPControllerScreen(
                  phone: _controller.text,
                  codeDigits: dialCodeDigits!,
                )));
              },
              child: Text('Next',style: TextStyle(color: Colors.white, fontWeight: FontWeight.bold),),
            ),
          ),

        ],
      ),
    )
  )

);

```