Z depth of cut gone haywire

my z depth of cut has started acting up after installing a new spindle with VFD. I have reached out to my software provider and they have checked a file I created and the file has correct settings. an already created and ran file that I know works was loaded and it now has the same z depth errors.

I suspect I may have accidentally changes parameters in the machine/controller? the software provider suggested I check the calibration and steps/mm settings are correct.

how do I access these on my controller and what should they be set at.