CNC Y-axis error

Hello guys,
i am exceptionaly asking for help, i have a little issue with my CNC, i am using a 7i76e Mesa running 3 axis, i experience a dimensional error in my Y-axis. I have 3 linear scales, the Y-axis has a linear of 5um resolution and a closed loop stepper motor attached to a 1605 ballscrew (16mm width, 5mm pitch), so my problem is that i have an "accurate" innacuracy that means my axis undershoot exactly 0,1mm in other words it mills 19,9mm instead of 20mm or 299,9mm instead of 300mm and so on... i dont know how to fix it without using Backlash = 0,1 because my ballscew has no backlash on the dial gauge. Does anyone has a simple solution on how to add 0,1mm to the .HAL file?
Thank you very much guys !

Thank you for your response Andypugh!
Saying that the target is a D10mm boring, it becomes D9.90 mm, if it is D10mm outer round shape it becomes D9.90mm (only in Y) X Axis is in both shapes D10mm

Yes they do say that they are in the right place

If i just could say to the machine net y-pos-cmd => pid.y.command + 0.1 it would be perfect but unfortunaly it's not that easy to add 0.1mm

[AXIS_Y]
MAX_VELOCITY = 116.666666667
MAX_ACCELERATION = 750.0
MIN_LIMIT = -0.01
MAX_LIMIT = 450

[JOINT_1]
TYPE = LINEAR
HOME = 0.0
FERROR = 10.0
MIN_FERROR = 1.0
MAX_VELOCITY = 116.666666667
MAX_ACCELERATION = 750.0
# The values below should be 25% larger than MAX_VELOCITY and MAX_ACCELERATION
# If using BACKLASH compensation STEPGEN_MAXACCEL should be 100% larger.
STEPGEN_MAXVEL = 156.25
STEPGEN_MAXACCEL = 937.5
P = 50
I = 0
D = 0.001
FF0 = 0
FF1 = 1
FF2 = 0.00073
BIAS = 0
DEADBAND = 0.001

And yes that is what i need, if i put in CAM a square with dimensions X 10 and Y 10.1mm i get Exactly 10x10mm and that also true for any dimensions like X500 and Y500.1mm i get Exactly 500mm in X and Y there is like missing 0.1mm but i dont know how to program it..