Although unlikely, with extended use it is possible for clogging in the chamber to occur. Please also keep in mind a variety of substances, consistencies, and flavors of essential oils can be used in the pen, as long as they are not overly runny, sappy or in liquid form.
To alleviate clogs you can unscrew the mouthpiece and hold the pen upside down over a paper towel or hold the pen upside down using your Prism, initiate Sesh Mode for a cycle or two allowing any bi product to drip out of the holes in chamber.
You may have to repeat this process a few times depending on how heavy of a clog you've experienced. If this is the case, let the pen cool every 2-3 Sesh Mode cycles as the pen will get warm!