Before dealing You already checked. You even brought along your drone and installed the batteries, checked the charge cycles (truely is below 30) and the batteries also works. NOW AFTER MORE THAN 1 WEEK, CLOSE TO 2 WEEKS to be exact and you complaint battery bulging? This is just too suspicious. As stated, I will never sell spoilt stuffs and would rather throw it away than to sell. All Sellers beware of such buyer. Don't recommend to deal with him if possible.