Firstly, you need to ensure that you are using a working charger - not a faulty one that must be held in a specific position to work. If the charger is fine, check your battery as that could be the next faulty thing. Try replacing the battery. If the issue disappears, it was the battery, however, if the issue persists after changing the battery then it must be something more serious. I would recommend that you then take it to your supplier who will run diagnostics and/or open the device to find the root of the problem.
Hope this Helps.