Help me please! Plasma cutting with -1.5 mm of error

Hi guys

I have got a table smart 2 Steel Tailor with SF-AH200 controller, running a hypertherm 105. The problem with the machine is that the external cuts are always 1.5 mm to 1.7 mm smaller than the programmed one, if I program a square of 100 mm x 100 mm the result is 98.5 mm x 98.5, I have already verified the parameter "Numerator" and it's fine because the interior cuts are good and distances between centers.

What should I adjust in the control to solve this? Do you have any idea?

Thank you