I am using a micro router pro. I have to jog the tool about 12mm below the Z0 for it not to give an error message

Hello, Since I upgraded to VR Milling version 5 I have had a problem setting the Z-Axis offset. If I do not set the Z-offset less than about 12mm below the bottom of the tool a Z-Axis error message comes up when I press exlamation mark in the program, this means that I can no longer machine as thick...