I bought my iPhone from a Sam's Club in November and have had no problems with it. 3 days ago it started randomly shutting down on me. Every time I have had over 50% battery left. When I try to power it back in it shows the battery with a red bar indicating that the battery is dead. The moment I plug it in the battery reads the percentage it did when it shut off on me (anywhere from 56% - 66%). Does anyone have any suggestions? Since i have had it for 3 months do I contact the Sam's club where I bought it from to see about getting a replacement or do I need to contact my phone carrier about that first? Any help would be appreciated.