Problem with NavigationLink

Could you post the complete code ?

Here the part on the start View:

TabView(selection: $selection) {
        NavigationView(){
            List {
                ForEach(alarmList, id: \.self) {
                alarm in
                    NavigationLink(destination: AlarmDetailView(alarm: alarm)){
                        HStack(){
                            SingleAlaramView(isAlarmOn: alarm.state, name: alarm.name, time: alarm.time)
                        }
                        .cornerRadius(5.0)
                    }
                }
                .onDelete(perform: self.deleteItem)
            }
            .navigationBarTitle("Wecker")
            .navigationBarItems(leading: EditButton())
            .accentColor(Color("accent"))
        }
        .tabItem {
                Image(systemName: "alarm")
            }.tag(1)

The SingleAlarmViews are shown in the NavigationLinks, here is the code:

struct SingleAlaramView: View {
    @State var isAlarmOn:Bool = false

    let name: String?
    let time: String

        var body: some View {

                HStack(){
                    VStack(){
                        Text(name ?? "Wecker")
                            .frame(width: 200, height: 20, alignment: .leading)
                            .font(.system(size: 22, weight: .semibold))
                            .lineLimit(1)

                        Text(time)
                            .frame(width: 200, height: 20, alignment: .leading)
                            .font(.system(size: 15, weight: .light))
                            .foregroundColor(.gray)
                    }
                }
                Spacer()
                Toggle("Alarm", isOn: $isAlarmOn).labelsHidden().padding(.trailing)
        }
}

Tapping a NavigationLink shows the following View:

struct AlarmDetailView: View {

    @State var alarm:AlarmItem
    @State var selectedTime:Date = Date()
    @State var isOn:Bool = true

    let settings = ["Bezeichnung", "Ton", "Wiederholen", "Schlummern"]

    var body: some View {
        let title = alarm.name
        let navTitle = title + " Details"

        NavigationView() {
            VStack() {
                DatePicker("Time", selection: $selectedTime, displayedComponents: .hourAndMinute)
                    .labelsHidden()
                    .datePickerStyle(.wheel)
                List {

                    NavigationLink(destination: NameSettingsView(title: "Bezeichnung")){
                            HStack() {
                                Text("Bezeichnung")
                                Spacer()
                                Text(title)
                                    .font(.system(size: 15, weight:     .light))
                                    .foregroundColor(.gray)
                            }
                    }

                    NavigationLink(destination: ReoccurSettingsView(title: "Wiederholung")) {
                        HStack() {
                            Text("Wiederholung")
                            Spacer()
                            Text(alarm.reoccur)
                                .font(.system(size: 15, weight:     .light))
                                .foregroundColor(.gray)
                        }
                    }

                    NavigationLink(destination: SoundSettingsView(title: "Ton")) {
                        HStack() {
                            Text("Ton")
                            Spacer()

                            if (alarm.fadeIn){
                                Image(systemName: "lessthan")
                                    .foregroundColor(.gray)
                            }

                            Text(alarm.sound)
                                .font(.system(size: 15, weight:     .light))
                                .foregroundColor(.gray)
                        }
                    }
                    HStack() {
                        Text("Schlummern")
                        Spacer()
                        Toggle("Schlummern", isOn: $isOn).labelsHidden()
                    }
                }
            }
        }
        .navigationTitle(navTitle)
        .accentColor(Color("accent"))
    }
}

This AlarmDetailView is shown fullscreen (would like to have it displayed like with "Show()" in Storyboard).

Now when tapping let's say "Bezeichnung" which is the name of the Alarm, it is shown with the previous NavigationBar still visible, like stacked. Here the code for the "settings":

struct NameSettingsView: View {

    let title:String

    var body: some View {

        NavigationView() {
            Text("Setting")
        }
        .navigationTitle(title)
    }
}

This View doesn't do much right now, I first would like to solve the presentation issue.