Hi Ihatememojis,
Thanks for coming to Apple Support Communities for help today. As we understand you aren't receiving notifications on your Lock Screen for text messages.
It does sound like you have tried some great troubleshooting. Please also see: Use notifications on your iPhone, iPad, and iPod touch.
"Open from the Lock Screen
You can see your recent notifications on the Lock Screen by picking up your iPhone or waking your iPad. You can also do these things from the Lock Screen:
- Tap a single notification to open the app that it's from.
- Tap a group of notifications to view all recent notifications from that app.
- Swipe left over a notification to manage alerts for that app, or clear the notification.
- Touch and hold a notification* to view the notification and perform quick actions if the app offers them.
To show the contents of notifications on the Lock Screen without unlocking your device, go to Settings > Notifications > Show Previews, and select Always."
Have you updated to iOS 15.2.1?
Have you checked for any Focus settings: Use Focus on your iPhone, iPad, or iPod touch?
Let us know.
Have a fantastic day!