It may happen that on the Samsung Galaxy S8 you make settings within the Android operating system, which then lead to certain functions no longer working properly. This is the case until you have changed the setting again.
If you have changed settings in Android and you do not know where, then you can generally reset all settings of the Android operating system. This works as follows:
1. From the Home screen, open the app menu, and then click the settings.
2. Tap "General Management" and then click Reset
3. Here you will find "Reset Settings". Select the option and then the "Reset settings" button.
This will reset all customizations such as ringtone, non-interference mode etc. to the basic settings. You should now have no problems with your settings on the Samsung Galaxy S8.