I have made the following circuit:
Viusalisation (not working): https://i.stack.imgur.com/tDA85.png
Left to right, the pins on the chip are: vcc out2 in-2 in+2 and ground at the bottom
It always powers the LED with 3.3 V no matter what the inputs are, so the LED is always on. The circuit simply doesn't change, no matter which line or none at all are plugged into the inputs.
It is powered by the 3.3 V and 5 V connections of a Raspberry Pi. The resistor is 10K, but I've tried it with 1K and 100R as well and the circuit still doesn't work.