Problem using stars ratings in Music

On my iPhone X with iOS 12 Beta (issue exists in all betas so far, i.e. 1-4) I've enabled the stars ratings in settings. When I have the 'Now playing' screen open in Music, tap on 'rate title' (sorry, my interface language is German, so that may not be accurate), the appropriate dialog opens and I can select 1-5 stars as expected. Closing the dialog with 'Save' (Done or whatever that right button reads in English) closes the dialog, but does not save my rating: reopening this dialog shows the empty stars again. This can be repeated with the exact same behaviour again and again.


I've tried disabling the rating in settings, and re-enabling it, but that did not help. Same on an iPad Pro 10,5" with the same iOS Beta. Any ideas?