where this white spot come out from my swiftUi view?

Question

I'm using a view modifier in my Form view in order to push up the view when the keyboard appears to avoid the keyboard hiding the text field, it used to work perfectly but I don't understand why suddenly when the keyboard appears there is a strange white padding.

As you can see the View going up but from the keyboard to the textfield appear a strange white spot, cant understand why and how to remove.

here my MainView

 var body: some View {
        
        
        NavigationStack{
            ZStack{
                // change view base on index
                switch selectedIndex {
                case 0 : Text("HOME")
                case 1 : Logbook(dm: dm)
                case 2 : AddFlightView(dm: dm)
                default: Text("Default")
                }
                // Overlay tab bar
                VStack{
                    
                    Spacer()
                    
                    BottomBar(selectedIndex: $selectedIndex, items: $items)
                        .cornerRadius(15)
                        .padding(.horizontal)
                        .shadow(color: Color.darkTextColorMain.opacity(0.1), radius: 10,
                                x: 10,
                                y: 5)
                    
                        
                }
            }
            .navigationTitle(titleChange(selectedIndex: selectedIndex))
        }
    }

My Add flight view where the Form that should move up is:

 var body: some View {
        
        Form{
           
                Section("Flight") {
                    Picker("Select ", selection: $selected) {
                        ForEach(DutyType.allCases,id: \.self) { type in
                            Text(stringPicker(dutyType:type))
                        }
                    }
                    
                    DatePicker(selection: $flightDate, displayedComponents: .date) {
                        Text("Select a date")
                    }.environment(\.timeZone, TimeZone(abbreviation: "UTC")!)
                }
                
                Section("Departure and Destination") {
                    
                    HStack{
                        Text("Departure Airport")
                        TextField(text: $departure_Apt) {
                            Text("Departure Airport")
                        }.multilineTextAlignment(.trailing)
                        
                    }
                    HStack{
                        Text("Arrival Airport")
                        TextField(text: $arrival_Apt) {
                            Text("Arrival Airport")
                        }.multilineTextAlignment(.trailing)
                    }
                    
                }
                
                Section("Time Selection"){
                    DatePicker(selection: $chockoff, displayedComponents: .hourAndMinute) {
                        Text("Chock OFF \(convertDateToString(date: chockoff))")
                    }.environment(\.timeZone, TimeZone(abbreviation: "UTC")!)
                    DatePicker(selection: $chockin, in: convertToUTCDate(dateToConvert: Date.now)... , displayedComponents: .hourAndMinute) {
                        Text("UTC Selected: \(convertDateToString(date: chockin))")
                    }.environment(\.timeZone, TimeZone(abbreviation: "UTC")!)
                    
                    TextField("Add", text: $test)
//                        .textContentType(.oneTimeCode)
                        .keyboardType(.numberPad)
                    Spacer()
                }
                
        }
        .modifier(Keyboard())
    }

and the ViewModifier that notify the keyboard change:

struct Keyboard : ViewModifier {
    @State var offset: CGFloat = 0
    func body(content: Content) -> some View {
        content.padding(.bottom,offset).onAppear(perform: {
            NotificationCenter.default.addObserver(forName: UIResponder.keyboardDidShowNotification, object: nil, queue: .main) { notification in
                let val = notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as! CGRect
                let height = val.height
                
                self.offset = height
            }
            
            NotificationCenter.default.addObserver(forName: UIResponder.keyboardWillHideNotification, object: nil, queue: .main) { notification in
               
                
                self.offset = 0
            }
            
            
        })
        
        
    }
}

here is what happens without the modifier... When the keyboard shows up it hides my text field in the form