Iphone 4s battery replacement
I got my Iphone 4s on a 3 year plan in February 2013. I have now had it for almost two years and the battery is beginning to act up. It will be at 10% and then die suddenly, and within minutes of plugging it in the battery will then jump to 25%. I've also noticed that the battery doesn't last nearly as long as it used to. I tried taking the phone to a jump+ store, however because it did not fail the diagnostic test they told me they would be unable to replace it although my apple care is good until late February 2015. I then tried calling apple to see if they could help me out. The woman on the phone ran the diagnostic test again and it didn't fail. She then gave me some tips on how to make my battery last longer like turning off location services. Can anyone suggest a way to get the battery replaced or am I going to be stuck paying off the remaining balance on my plan and getting a new phone? Thank you!
iPhone 4S, iOS 8.1.2