Careful with it, then. It's sensitive, so be very selective of the areas you decide to open up. And by open up I mean just barely shave off the dried parts on the corresponding halves until the 'sap' comes up.
Remember, both halves that meet must be moist with the blood and viscera of the plant, and then moistened with water before being taped. This time, make sure it's tight, but not so tight that it restricts the stem's nutrient/water uptake efficiency.
..Sorry, there was no gentle way of putting that first part. I couldn't help myself.