There are some things you can do if you are not getting complete cuts.
Make sure the material is flat against the tray, either by using shielded magnets or the Honeycomb Pins located here.
Make sure the lenses and windows on the head and under the left side are kept clean.
Test a cut before moving the material on the bed with a little rolled up piece of tape or a pick of some kind. If the cuts don’t lift out clean, you can send a second pass of the cut. If you do not let the material shift on the bed or try to realign the artwork on the screen, the second cut will land perfectly on top of the first one and finish it.