Do you own a Yocan UNI?
If also have Yocan UNI vape mod flashing error, similar with this Yocan user, please read this thread.
I bought the yocan box vape maybe 3 weeks ago. It charges, it heats up, lights flash, but I can't get vape from it. So far I'm not finding my issue anywhere. Please help.

Answer:
Thanks for contacting us.
How many times does the light flash when you hit the fire button?
The battery flashing 5 times means no atomizer error, the Yocan UNI battery can't detect the vape cartridge.And the UNI battery flashing 3 times means short-circuit error.You can try to  switch the vape cartridge or loosen the adapter.