It doesn't sound like you are selecting a work offset to use. Type G54 to G59 into the MDI to activate a work offset.
While you can directly edit the offsets keep in mind that the offset is intended to transform from machine coordinates (often where the limit switches represent 0,0,0) to a reference point on the stock (probably a corner).
What you want to achieve would be more easily done with tool length offsets or maybe a G52 transform. I also would make a general recommendation that you generally don't need to edit the work offsets by typing numbers into the table. Typically you are setting work offsets with an edge-finder or probe, or you can even just type a new number directly into the axis readout to alter the active work offset.
https://www.cnccookbook.com/g54-g92-...ts-cnc-g-code/