Hey there VictorLJr,
Thanks for reaching out to Apple Support Communities. I understand you’re not getting Message notifications on your iPhone. It sounds like you’ve done some great troubleshooting so far and I’ll be happy to help.
Based off the troubleshooting you’ve already completed, the next step would be to ensure your iPhone is up to date:
Update your iPhone, iPad, or iPod touch
If it’s already up to date, back up your iPhone and reinstall iOS using the steps from these links:
How to back up your iPhone, iPad, and iPod touch
If you can't update or restore your iPhone, iPad, or iPod touch
If you still have issues, restore your iPhone to factory settings then adjust the message notification settings:
Restore your iPhone, iPad, or iPod to factory settings
Change message notifications on iPhone
This will remove your Wi-Fi password and connections and you’ll need to set those up again once the restore is complete.
If the issue doesn’t appear in factory settings, restore your backup and test once more:
Restore your iPhone, iPad, or iPod touch from a backup
Regards.