Hello JodyCampbell,
If the Face ID on your device is not working properly, you can follow these steps: If Face ID isn't working on your iPhone or iPad Pro
If the device is having performance issues, like running slowly or becoming unresponsive you can use these steps: If your iPhone or iPad is running slow
If you have multiple iPhones and your messages/calls are appearing on all of them, that would mean that you're currently signed into the same Apple ID on all of them. If you do not want your calls and messages to be delivered across your devices, then you'll want to sign out of the Apple ID on those other devices and use a different one on them.
1. Go to Settings, then tap your name.
2. Scroll down to the bottom.
3. Tap Sign Out.
Sign out of iCloud on your iPhone, iPad, Apple TV, or Mac
Cheers!