A Yocan Hit fan told us about no smoke issue.
Here is his or her question:
When l take my hits and it’s been quite a few never seen any smoke.

You have to check the Yocan Hit device turn on or not.
5 taps the fire button to turn it on/off.

Then check the chamber, make sure the dry herb loaded bottom of the Yocan Hit chamber.
Switch the vape mode(3 min/5 min), and you can see the temperature increase on the OLED screen.

Once the device vibrated, you can inhale it.

Any further question, please comment below.