Hi. My name is*****'m a camera repair technician with almost 30 years in the business and I'll be glad to help you with your question today.
If you are sure the battery is fully charged then the problem is electronic in nature. This is going to require disassembling the camera to troubleshoot and repair by an experienced camera repairman. You may want to check locally for a camera repair shop in your area, or, if you need assistance finding a shop, please let me know and I'll locate one for you.
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