I received my BPM Connect device last night and proceeded to plug it in with the provided Micro-USB cable. Upon waking up this morning it still says that the battery is drained and I have no indication it charged. I downloaded the user manual and see it only says it takes 3 hours to charge... I swapped the cables to one I know works and still no indication it's charging. Here's my question: How do you know the device is charging?