iPhone Unavailable and i can't restore it

Hey there. Try the following:

1) If your issue is regarding forgetting the passcode and being locked out, see here for reset instructions: If you forgot your iPhone passcode - Apple Support

2) If you are looking to reset the device to factory settings, see here: Restore your iPhone, iPad, or iPod to factory settings - Apple Support

3) If you reset your iPhone and you have an iCloud backup, see here for restore instructions: Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

Let me know if any of these helped.