Hey there sagarshah1983,
Thanks for reaching out to the Apple Support Communities. To get started, have you ensured that all the settings for the apps are set up correctly using the 'Related Article', Use notifications on your iPhone or iPad - Apple Support that was shared on this thread?
For this particular issue, we'd recommend ensuring that you have a notification sound selected for the apps you're not hearing notifications for using the steps under the "Change alert styles " section.
Change alert styles
1. Go to Settings and tap Notifications.
2. Select an app under Notification Style.
3. Under Alerts, choose the alert style that you want. If you turn on Allow Notifications, choose when you want the notifications delivered—immediately or in the scheduled notification summary.
With iOS 15 and iPadOS 15 or later, you can turn on Critical Alerts for supported apps so notifications come through even if your iPhone is muted or you have a Focus set up.
If still having issues, we'd also recommend checking for any Focus features that may be enabled and preventing notifications from being received as expected. For help with checking your Focus settings, check out this next link here: Use Focus on your iPhone or iPad - Apple Support
Keep us updated on the results.
Have a great day!