it has a built in battery so how the fuck do you charge it like
@rew said
Think it is a classic case of "some" shops/assistants not knowing their arse from elbow etc...
Yes with mods taking replaceable 18650's etc... the general advice is to charge them externally
Though most respected modern mods allow you charge them via usb at times
(hence they provide a usb port to charge them with)
Though most still charge 18650's externally....
Charging a single 18650 in situ in a modern trusted mod is OK where necessary if needed
it is when you charge a dual 18650's in a lesser known mod it becomes a little risky
as with dual battery mods, they do not balance the batteries like a quality charger can
So the general advice is for mods with replacement/external batteries - should be charged separately
The device in question has an internal cell, so me thinks the person was unaware where there elbow/arse was located