iTunes won't recognise iPhone XS after update to iOS 14.3

I have iPhone XS and just updated to iOS 14.3 - overnight my MacBook Pro 13" early 2015 running Sierra 10.12.6 won't recognise my phone in iTunes. I've tried using MobileDeviceUpdater but the App won't open. I've tried connecting to wifi and doing a computer/phone restart. Any help would be massively appreciated.