swiftui - SwiftUI .onTapGesture does not work until list is scrolled

Question

I have a Textfield used to name doorways. You tap the textfield and a list is unfolded below with a list of common room names. I can't select an item from the list until after I scroll the list.

Here is my code:

internal var body: some View {
    ZStack {

            VStack {
            
                HStack { /// the text field
                        TextField(self.namePlaceholder, text: $viewModel.name)
                            .onChange(of: viewModel.name) { newValue in
                                typedRoomName = newValue
                            }
                }
                .onTapGesture {
                        showAutoRoomNames = true
                }
                    
                if showAutoRoomNames { /// the list of common room names that gets filtered as you type
                   VStack(alignment: .leading) {
                        List {
                            ForEach(RoomNames.getFilteredCommonRoomNames(prefix: typedRoomName), id: \.self) { n in
                                Text(n)
                                    .onTapGesture {
                                        
                                        viewModel.name = n
                                        
                                        if showAutoRoomNames {
                                            showAutoRoomNames.toggle()
                                        }
                                    }
                            }
                        }
                        .listStyle(PlainListStyle())
                   }
                }
            }
            .padding()
            .frame(maxWidth: 300)
            .zIndex(2.0)
    }
}

}

So if I tap the text field, the list of names unfolds, and if I start entering a name I can tap a filtered name. But if I don't start typing a name, I can't select an item from the list until I scroll the list.

The .onTapGesture block in the showAutoRoomNames block does not get hit until after I scroll, I don't know why.

Thanks for any pointers.