Today one of my JDs in my class would not turn back on. I unscrewed JDs back to double check all connections in his body and everything is intact. JD never indicated that it was on low battery after all JD was charged overnight. I've adjusted the female pins as shown in the video even though I didn't think that was the issue. This JD worked early in the period and sporadically stopped working. In addition to that, the power button is flipped upside down (this is how it was when we opened the box but it did not affect its function). Has anyone experienced this problem before? Regardless what should I do?

Thank you for your response in advance.