AutofillHints.email not working as expected?

It pops up with my icloud email but doesn't know my gmail address, the email I registered with. How can I get it to remember? Using my iPhone 8 as a simulator, running iOS 15.

Following this 5min tutorial: https://www.youtube.com/watch?v=v8T4fnrQCf0&ab_channel=JohannesMilke

And this article: https://medium.com/swlh/how-to-implement-autofill-in-your-flutter-app-b43bddab1a97 they said:

I tried downloading the google app for autofill settings, I couldn't get it to work. And I would like my users to be able to autofill without downloading another app if possible. Is there more code I can add to achieve a look like this?

SingleChildScrollView(
              child: Container(
                padding: EdgeInsets.symmetric(vertical: 100, horizontal: 50),
                child: Form(
                  key: _formKey,
                  child: AutofillGroup(
                    child: Column(
                      children: <Widget>[
                        SizedBox(height: 20.0),
                        TextFormField(
                            autofillHints: [AutofillHints.email],
                            keyboardType: TextInputType.emailAddress,
                            textInputAction: TextInputAction.next,
                            style: TextStyle(
                                color: Colors.white,
                                fontWeight: FontWeight.w300),
                            cursorColor: Colors.blue[100],
                            decoration: textInputDecoration.copyWith(
                              hintText: ('Enter Email'),
                              hintStyle: TextStyle(color: Colors.white),
                              enabledBorder: UnderlineInputBorder(
                                borderSide: BorderSide(color: Colors.white),
                              ),
                            ),
                            validator: (value) {
                              if (value!.isEmpty) {
                                return 'Email is required';
                              }
                            }),