One of the things that I like to use to check to make sure that something has cut completely through is something like this inexpensive vinyl weeding pick:
Try to lift the center cut without shifting the backing material. If it does not come out, just re-run the Cut portion of the job without shifting the design or the material on the bed…it will re-cut a second pass right over the top of the first one and save the job.
The trick is to not shift either the material on the bed or the design on the app screen. (Which is why the Honeycomb Pins are invaluable.)