Hello lenexa909,
To help troubleshoot the behavior, ensure banners are enabled in the notification settings for the apps you're using.
If notifications are enabled for your apps, then disable the notifications, wait 30 seconds, and then turn the notifications back on and test. Check out how to access notification settings here: Use notifications on your iPhone or iPad - Apple Support
"Change alert styles
- Go to Settings and tap Notifications.
- Select an app under Notification Style.
- 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."
To further troubleshoot, ensure the date and time setting are set correctly, ensure a Focus state isn't enabled when you're expecting notifications as that can silence them, and test after turning off all of your devices for at least one minute and then powering them back on:
If the issue continues, then reach out to Apple Support for further assistance with the behavior: Contact - Official Apple Support
Kind regards.