I'm sorry to hear you are having this issue. I have seen this a handful of times with other phones. To save you the time of trying to troubleshoot the issue, I would recommend going into an service and repair center so they can test the battery and the phone. Below is a link to our store locations. please select the radio dial that says repair to give you the correct listing.
I would advise you to go to a Sprint Service and Repair store so they can test the device and the battery. It could be one or both.
Hope this helps,
Sprint Advanced Tech Support
Did this help? If so please rate this post and mark your post as answered so others can refer to it quickly for solutions
Help prevent distracted driving. Get Sprint Drive First FREE at the Google Play Store.