Question about Panasonic Dmc-Tz101

I bought this camera about 2 years ago. Very satisfied. However, the following happens now: If I don't use the camera for a while, the battery empties itself. (The camera is logically switched off). When I want to charge the battery again, the red light simply flashes, i.e. the battery is not charging. I have already bought a new battery twice - always the same. I have never had this with a camera before - is this a defect? Why is it like this? Experiences?