help

If iTunes doesn't recognize your iPhone, iPad, or iPod

1. Make sure that your iOS device is unlocked and on the Home screen.
2. Make sure that you have the latest version of iTunes that works with your computer.
3. Check that you have the latest software on your Mac or Windows PC.
4. Make sure that your device is turned on.

If you use a Mac

1. Connect your iOS device and make sure that it's unlocked and on the Home screen.
2. On your Mac, hold down the Option key, click the Apple menu, and choose System Information or System Report.
3. From the list on the left, select USB. 
4. If you see your iPhone, iPad, or iPod under USB Device Tree, get the latest macOS or install the latest updates. Then uninstall third-party security software. If you don't see your device or still need help, contact Apple Support.
5. 

If iTunes doesn't recognize your iPhone, iPad, or iPod - Apple Support

https://support.apple.com/en-us/HT204095