For Android devices please activate the “Notifications in background” option from the setting menu, found in the site list screen. For IOS devices, please login to your site, go to push notifications settings menu and tap on "Restart Push ...
Unfortunately, right now Apple’s APIs do not allow our app to override Do Not Disturb mode or the system volume on iOS. If this changes in the future and Apple exposes public APIs for this, we can investigate ways to implement the feature to override ...