Most dab pen use don't know the right way to clean the Evolve series product.
Here is a Yocan.com fan's question.
Hello, I recently purchased the Evolve D Plus Dry Herb Pen and am noticing residue buildup in the mouthpiece. It is also getting clogged from time to time where there seems to be no airflow. I have used the brush but it seems to not fix the issue. What other ways am I able to clean the mouthpiece? Are qtips and alcohol acceptable? If not, what other materials can I use to remove the residue buildup. Thank you in advance
Yes, please try to use a q-tip with isopropyl alcohol to clean the mouthpiece.
And please dry it completely when you screw it on the Evolve-D battery.