Why are my iPhone notifications not popping up?

Then please check the following.

• Check your DND status - Settings > Focus [Do Not Disturb]; Use Focus on your iPhone, iPad, or iPod touch - Apple Support
• Check BedTime Status - Clock App; Use Bedtime to track your sleep on your iPhone - Apple Support
• Check your iPhone Sound Volume; Adjust the volume on your iPhone - Apple Support
• Check Call Audio Routing; Call Audio Routing Bluetooth / Speaker / Automatic
• Check Auto Answer Calls; Turn off Auto Answer Calls
• Check the list of Blocked Numbers --> Block phone numbers, contacts, and emails on your iPhone ...

Notification Preview when Screen is Locked, Notification Alerts, Notification OFF, and much more...

1. To get Notifications when the Screen is locked see the pic below which is self-explanatory
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2. To turn ON notifications selectively for apps, go to Settings > Notifications > Scroll Down to the App and turn ON notifications... Change notification settings on iPhone - Apple Support (IN)
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3. Some apps have their own notification settings over and above the iOS notification settings: An example of Instagram Notification settings is given below
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4. Help for Notification Alerts --> No Notification Alerts - Apple Community

We all know it’s an Apple problem with IOS I’ve been told we have to wait for new update. Months now. Apple has lost all respect and if they can’t fix by now then……

Here’s what I got. Receive a text with sound/notification. I respond with my text. They respond with no sound/notification on iPhone or smartwatch. What gives?