send to port 12002:
/serialosc/list localhost 8080
you should see the device port.
then to the device port send:
/sys/port 8080
and then make sure it worked
/sys/info 8080
the buttons working means you have this stuff already set up though. you’re likely not sending the LED data to the right port. send LED data to the port reported by /serialosc/list
good luck!