Logitech G13 mini joystick Y axis inverted on soldier movement

HI all. Need some help here.
I use the G13 gaming keyboard, from Logitech and to get the most of the soldier movement, I chose the mini joystick option instead of just assign it with WASD keys. This is the best way for using analog movement. But for some reason, when I pushing forward with the mini stick, I'm going backward. When I'm pushing the stick backwards, I'm going forward and I can't find any option to invert or to bind joystick axis to soldier movements.
In the Logitech software it's impossible to inverted this axis, so my question is, is there any solution for this?

Thanks in advance.
Marco Martins