本文发表在 rolia.net 枫下论坛The answer is 1: The over load protection setting is too sensitive (when door only move small distant.)
2: The door is also set too much travel for the closing (over travel)

Yes. You can do it your self.
Found the turning knobs on the door opener, it should have 4 of them in most of the models, two "knob” marked with an arrow. One down and one up. . Turn the up arrow clockwise, to change the open and closing travel distant. This will fix up the door reopen when it hit the ground when closing.

The other two knobs are for the load setting, which marked with a circular arrow, clockwise and counterclockwise,
Counterclockwise increase the load. Clockwise to decrease the load,

Try it both why half turn each time, to found the proper setting, try it few time. (Remember this, no matter which way you turn, make note on how many turn you make, by remember this, in case if it do not make it better, then you always can go back to the original position)

This give an idea, you should read the owner manual more info is there更多精彩文章及讨论，请光临枫下论坛 rolia.net