Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
I think I can explain the situation, after a few questions, and perhaps instruct you how to fix the problem yourself.How old is your Kindle please?
It might have a defective battery. Try turning it On, while it is connected to a charger, and see if it behaves differently or 'lasts longer' before turning Off.
Let me know, using the Reply To Expert function, and I will advise you. Thanks.