@kamrulhasan we need to see what is going on with your battery contacts. Post some pictures of what you got going on there with your question [guide|21499] That way we can see what you see. It could be as simple as replacing the battery to as complicated as replacing the battery connector. Hard to say without seeing it. Use something like [https://www.youtube.com/watch?v=bUQcp0Ypndg|this video] to replace/work on your battery connector.