I have just looked back at your previous email communications with tech support and can see that you were intending on sending your device in to be inspected but decided not to do so. If you have any concerns about the functionality of your device, taking up the offer of a free inspection and service so that we can confirm your device is operating as intended is the best move forward.
I would like to stress here that it is normal for the Dekunu One battery to drain when powered off, there are some things you can do prior to powering the device off that will reduce the amount of depletion such as disabling the wifi connection and by charging the unit with either a Dekunu branded or well known branded micro USB cable at a strong power source for best charging results.
I am not sure that the responses on the forum are achieving a positive result for you and I would very much like to resolve any issues you are having and ensure your happiness with your One, so my suggestion is to send in your device to rule out any faults and put your mind at rest. If you do not wish to do that, I completely understand - the only thing I can do to help you in this case is refer you to the tips above.