Noob help needed setting up Novation Circuit tracks midi 3 or 4 as input

Ive got a circuit tracks which is able to output to other hardware on midi 3 & 4 which I am trying to configure.
Cantabile is working well with onscreen keyboard but selecting input port to midi in on either omni track 3 or 4 using a midi to usb cable is showing no input.
The device is detected and selectable as in this example arp 2600 - Midi In
Is there something I am missing or anything I can use to check the cable is working please