New Juul got a little warm while first charging it

Hi so i grabbed a Juul from the gas station and plugged the charger into my pc , and so it was blinking when i put it on the charger, and it was on maybe an hour or so until it got solid light. But when i took it off , i noticed it was a little warm to the touch which surprised me a bit. Just wondering if anyone seen this or if this could some kind of issue. Thanks for any help

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