I ordered a replacement battery for my iphone 3gs that is 13 month old.
After replacing the new battery it last less than the original iphone batter by at least 3 hours, and the original battery is 13 month old!!!!!!!!!
Had to put the original battery again:)
VERY VERY VERY BAD Product:)
Did you contact iFixit support about your issue? It's not hard to do, you should have gotten an email about 10 days after your order to make sure everything was ok. If it's not a replacement or refund will be taken care of ASAP. Actually contacting a companies support when you have an issue to see how they handle it instead of posting it publicly on their webpage is the correct way to handle a situation like this.
Also, did the battery get fully charged after being installed or just installed and used? Did the phone usage change? Did you do a restore on your phone after installing the battery? There are lots of user variables that come into play with a new battery that support would be able to help you resolve.
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