I purchased a M2Z three weeks ago and on its second flight, the voltage dropped from 65% to 10%, an alarm sounded and an on screen warning displayed and then the voltage jumped back above 60% after I panicked. The log showed absolutely nothing. ?. I am now flying with guarded caution. I reported this in this forum.
It's not possible for an event that caused a screen warning not to have been recorded in the flight logs. The warnings themselves are recorded.