Q: I have problem in notifications don't work

Hello Badr Nabil,

Thanks for using Apple Support Communities.

I understand you're not hearing notification sounds from some apps.  Please make sure they are configured to give an audible notification by checking your notifications settings.

Change Notifications settings 

Some apps like email or social media apps send frequent notifications, which might affect battery life. If you have Show on Lock Screen turned on for notifications, this also might affect battery life.

To turn off or change notifications, go to Settings > Notifications and select the app. You can also sort your alerts by most recent, order them manually, or group them based on the app.

Use Notifications on your iPhone, iPad, and iPod touch

Take care.