I’ve never understood the desire to save a few bucks on
batteries which are THE most important part of a vapers setup.
People will spend all sorts of money on gear yet cheap out on batteries. Not saying the OP did just what others have done based on my observations.
The ONLY way imo you have the best chance of purchasing authentic batteries is to buy them directly from a reputable battery dealer. Not a vape store and definitely not from EBay.
When in doubt - recycle them and get new ones.