I've probably done almost 100 flights and this new thing happened a couple days ago. Flying maybe 300meters from home and pressed "return to home". Mavic went to the usual 90m and started cruising back normally. I cancelled "return to home" just as the Mavic started descending and it stopped and hovered. Started lowering manually with the stick and the Mavic started autolanding at 90 metres. This was not over water but rather a grassy backyard. Stopped the autolanding with the sport mode switch and it stopped descending, but as soon as I tried manually descending it again...the same thing happened. This time I just let it land, which took forever from almost 90m. Tried a new flight right after this and could not duplicate the problem. All sensor settings were at defaults. On an unrelated note...this forum saved my drone as I have experienced this autolanding thing over calm water, and was able to stop the drowning by using the sport mode switch as learned on the forum. Thanks!!.