SwiftUI DatePicker size not configurable

Hey guys,

I'm totally new to Swift programming and I'm setting up a view for registering users. I use a VStack to organize the TextFields as well as a DatePicker, but the last one seems to be very rebellious.

Here's my code:

        VStack {
            TextField("E-Mailadresse", text: $mail)
                .frame(height: 30)
                .textFieldStyle(.roundedBorder)
                .multilineTextAlignment(.center)
                .focused($hasFocus, equals: .mail)
                .onKeyPress(.tab, action: {hasFocus = .password; return .handled})
            SecureField("Passwort", text: $password)
                .frame(height: 30)
                .textFieldStyle(.roundedBorder)
                .multilineTextAlignment(.center)
                .focused($hasFocus, equals: .password)
                .onKeyPress(.tab, action: {hasFocus = .name; return .handled})
            TextField("Name", text: $name)
                .frame(height: 30)
                .textFieldStyle(.roundedBorder)
                .multilineTextAlignment(.center)
                .focused($hasFocus, equals: .name)
                .onKeyPress(.tab, action: {hasFocus = .prename; return .handled})
            TextField("Vorname", text: $prename)
                .frame(height: 30)
                .textFieldStyle(.roundedBorder)
                .multilineTextAlignment(.center)
                .focused($hasFocus, equals: .prename)
                .onKeyPress(.tab, action: {hasFocus = .birthday; return .handled})
            DatePicker("Geb.:", selection: $birthday, displayedComponents: [.date])
                .datePickerStyle(.wheel)
                .clipped()
                //.focused($hasFocus, equals: .birthday)
            Button("Registrieren") {self.register()}
                .padding(.top, 20)
                .keyboardShortcut(.defaultAction)
        }
        .frame(width: 375)
    }

And this is how it looks like:

As you can see, neither is the DatePicker centered correctly (it's more left located) nor is it clipped (reduced). I also tried adding a .frame() to itself, then I was ably to reduce it to the preferred height, but I can' reduce its width and as a result of this, I can also not write a full label like "Date of Birth" or something, because the wheel of the DatePicker always overlays it...

Is that a kind of misbehavior or am I missing something?

Thank you very much in anticipation for your feedback!

Kind regards

Kevin