USB-C plugs are supposed to have 2.0 data pins only on one side. It is only the sockets that should have them on both sides. The other data pins are negotiated.

USB-C plugs are supposed to have 2.0 data pins only on one side. It is only the sockets that should have them on both sides. The other data pins are negotiated. When USB-C was brand new, I got a flawed breakout board where only the socket's data pins on one side were connected. I did not notice it until it was soldered together and the device got power but no connection when the cable was connected in one orientation. But then I had already built a metal case to fit that breakout board perfectly, so I just left it in.