I have a new mavic pro battery, due to over half year to open box, the battery can not charge,
When I plug in the charger , the battery only flash the lower one light , flash 15 times, then stopped (can not charge).

out of warranty, how to fix it ..

Please help

Hi Stephen, sorry for that case happened. Normally, the damaged battery is unable to be repaired, what's more, you are not recommended to repair it because of the cost of the repair almost the same as to buy a new one. So it will be better for you to purchase a new battery for your drone. If there is any further issue, please feel free to let us know, we'll here for help.

I have 2 of this status batteries....   

Stephen Hung Posted at 2018-4-17 00:01
I have 2 of this status batteries....

my charger sometimes will not charge,  it seems that the connecter is loose and has to be fiddled around with, but it eventually starts charging,