My cell is china bt whn I attached my charger pin to slot it swtch off nd nw itis not strting?

help me please ......

Is it possible that the polarity on the charger could have been reversed in some way?

So much of what it would take to answer this question would require knowledge of how that particular device works internally. Unless someone else on EHelp has that knowledge, I would contact the place where you purchased it.