SD automatically logs flights when airspeed goes above threshold and works fine in flight. When I land I always stop navigation and then  backup track logs to cloud from the planes Android tablet, with an Internet connection from the sim card. Most of the time this works fine and I can review the tracks and logbook on another device later. 

It's hard to say. I think we need to narrow down what the problem is: are the flight logs missing on the device in question, or are they not getting backed up to the cloud? If the former, it would be worth your checking after landing to see if the log exists. If it doesn't for some reason, is there anything unusual about the flight just undertaken, or about the device when you were undertaking it?