The Lighting Controller

Hello I just purchase may D512S et I have a MacBook Air.
I only have USB C on my MacBook and I have to plug a switch to connect my D512S (coming with USB2 Cable) so when I connect my D521S only power is ok! The Led corresponding to USB is not working?
How can I do?
Thanks

The USB LED flashes only when the software communicates with it.
Does our software show "Interface xxx found" in its welcome screen ?