Hello Aman2310,
After reviewing your post, it sounds like you are not receiving notifications for a specific app. I would recommend you use this article to help troubleshoot the issue.
To get notifications, connect to a Wi-Fi or cellular network. If you still don't get notifications for a specific app, try these steps:
- Make sure that the app supports notifications. Go to Settings > Notifications, select the app, and make sure that Allow Notifications is on.
- If you have notifications turned on for an app but you're not receiving alerts, you might not have Banners selected. Go to Settings > Notifications, select the app, then select Banners.
- Make sure that you’re signed in to your Apple ID.
- Make sure that Do Not Disturb is off.
- If you’ve recently installed an app or restored from a backup, open the app to start getting notifications."
Use notifications on your iPhone, iPad, and iPod touch
Please don't hesitate to let us know if the steps resolved your issue or if you need additional assistance.
Thank you for using Apple Support Communities. Have a nice day.