Complete Fehlkonstruktion

I have now already the second brush (after conversion), the self-employed on and off again after about 1 week. The meantime, they can no longer turn on. I am now really just the fact that they come back on and completely empty runs (so it was during the first brush). I already have such a toothbrush (externally completely identical, the same brush head attachment if man disregards of the long part), then I bought them under the name Dentasonic Carrera. That is now already 5 years, and this works just fine. This new brush but some of it is probably went wrong with purported to improve. From the purchase of this toothbrush I can only advise.