HobbyStar 4600mAh 22.2V, 6S 35C LiPo Battery

I purchased this in the winter and checked the cells were ok. 3.7v- 3.8v average storage. But did not actually charge it till late summer. Guess what,one cell changed way faster than the others.It even hit 4.21 at times. I was just asking them to look at it because it was past the return period. I got a big F/u from them and had to toss my never flown lipo in the trash.RC Juice blows, and so does your lipo's