NavigationService won't navigate after going there via absolute Navigation

Question

I am currently working on a Xamarin.Forms application that is targeting UWP, iOS and android.

After implementing a login dialog I am navigating a logged in user to a SomeContentPage, which I now want to be enclosed into a NavigationPage (and perhaps later on inside a MasterDetailPage).

I am trying to reset the navigation stack by using a /-prefix for a absolute navigation route, which will bring the user to the desired page and clear the stack:

await NavigationService.NavigateAsync("/NavigationPage/SomeContentPage");

Following, from this page there is no more relative navigation possible:

var navigationResult = await NavigationService.NavigateAsync("AnotherContentPage")

It seems like that there is everything going well "inside" the navigation system (navigationResult.Success is true) but the app is not navigating to the AnotherContentPage at all.

If I navigate without the /-Prefix, the upcoming navigation calls work as expected:

await NavigationService.NavigateAsync("NavigationPage/SomeContentPage");

I am really concerned and I already investigated very hard on this.

I don't know if I am just not understanding something properly in the Prism.Forms NavigationService concept or if I am trying something impossible here.

I re-read the Prism.Forms documentation, watched several YouTube-tutorials and read many blog posts about navigation in Prism.Forms.

I am near to desparation right now.

I really feel bad asking this and I am really questioning my internet-research-skills at this moment, but it would be great, if someone of you could give me some advice, how to handle this.

Thanks in advance and have a nice day!