Mophie Juice Pack Plus - Charging Problem

My Juice Pack Plus is not charging to it's fullest four LED lights. This is a new case (factory in the box) that I just received about a week ago. It would charge to it's fullest initially, but not anymore. This is the second case that I bought on Ebay and returned that does this. I have tried different chargers and removing the case from the phone, but no progress. I can charge the case for eight hours overnight and I still only get the two LED's. I'm sure I won't get any warranty coverage from Mophie since it was bought from a private seller on Ebay. Any advice?.....Thanks

Probably a Counterfeit

My advice is quite buying from ebay sellers who often sell counterfeit goods. I would call Mophie's customer service, if you have a counterfeit, they will probably give you a coupon for a discount for a real Mophie. Happened to me, should have known that paying less than half-price I could get a counterfeit. I know now. Buyer beware.

Well, you were right! The case was a counterfeit. It was a very realistic "fake" compared to another Mophie case that I have. It actually came in the sealed factory box with the charger and instruction manual. The Ebay seller had 100% positive feedback. Someone is does a really good job making these "fakes". I actually sent the case to Mophie and they deemed it counterfeit. It sounds like they keep the fake case, but offered me a 40% coupon for another case when purchased directly from there website.

Bought my Mophie from Apple store and it not charging.

I bought my Mophie from Apple store and it not charging my 4S. I tested my friend's iPhone 4s and it is working fine. I got a replacement from the store and it is still not charging. It nothing to do with fake version , it is something wrong with my 4s and I do not know what's the issue?
I have the latest version of IOS 5.1