SuperTuxKart and second keyboard on my Laptop

I have Toshiba Satellite L850 laptop that runs Kubuntu 18.04. I have PS2 keyboard connected to my laptop via USB through a converter bridge that connects PS2 mouse too

The keyboard and the mouse are working perfectly, but in SuperTuxKart the acceleration button (What ever its button is, i.e UP, A, etc) should be pressed and released continuously to keep acceleration using the regarded external keyboard when using the left or right direction or pressing any other key, but using the laptop's built in keyboard it works as usual, i.e keeping the UP key pressed will keep the acceleration.

This is a configuration screen shot that shows up only one keyboard