Chosen Solution
I have an HKC model# P776A and if the charger is not in it will not boot up and when it is booted up you can take charger out but the battery drops fast.
kitten28608 going with the symptoms you are describing, this is a bad battery. It does no longer hold a charge. Replace the battery and re-evaluate. If nothing else it will give you a known-good starting point for further troubleshooting. Here is the guide for it HKC P776A Battery Replacement
