This means that your iPhone USB Lightning Cable not allow you to connect to the MacBook Pro. But there are other solutions ...
In this article we explain how to connect and / or charge your iPhone in your new MacBook Pro.
USB to USB-C
This simple adapter converts a Thunderbolt port 3 into a USB port, so you can connect your iPhone, iPod or any other device. You can find it on the Apple website for 25 € and there are other options more affordable third.
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