Unable to set notification channel settings on sheltered apps

[Byolock]

I can't change notification channel settings on my xiaomi 13 (HyperOS, Android 14). If I open the Notification Settings I can toggle if notification should make a sound or not, but notification channel setting like for example "Calls" with the Microsoft Teams App can't be changed. The click on "Calls" gives an error message from the settings app : "The App was not found in the list of installed apps" and therefore I can not change any notification settings for calls from the teams app.

Is there any known workaround? I've searched for similar issues but did not found anything.