Samsung Galaxy Discover -- Battery SUCKS?

I don’t know if the battery life on my Samsung Discover android is normal; I’ve already had it exchanged and the second phone I got—though they promised it was going to be better—is exactly the same. Battery drains after about 9 hrs of light texting and disabled data / wifi. Usually the first 40% will drain on sleep mode in about 2 hrs or less.

I’m a bit stuck because I bought a damn warranty for this phone and a cover, so I feel like I screwed myself over. I’m just trying to go through the steps recommended to me—drain 3 times / re-charge 3 times—and hope it gets better. I also disabled all of the apps.

I honestly feel like I got screwed over by BestBuy