Hiya I have a fujifilm e-900 I have used the

hiya I have a fujifilm e-900 I have used the camera less than 20 times. The last time I used it I had no problems at all. I had left it sitting in it's case for 6 months. Now when I try and us it I get the hand with lightning bolt on the lcd. Which I assume means the battery encasement is open. It isn't open. The camera turns on no problem then when I try and use any function it shuts down. How do I fix this?