Can't sync phone to iTunes on laptop
I plug my iPhone XS into my MacBook Air, and it tells me that I need to have install OS X 10.11.4 (or later) in order to use my iPhone with iTunes, but both my laptop and phone have the latest software updates (12.1 for my iPhone, and MacOS High Sierra for my laptop.) I'm using the Apple charge cable, and I've restarted both the laptop and the phone after the updates, and still nothing. I am not the most tech savvy person, and so am pretty clueless on what to do.
iPhone XS, iOS 12.1, My laptop is a MacBook Air