I've had that happen twice on my car. Good thing those times were under warranty. The last tech who came out said it's a design flaw, and it will happen again eventually. What I can share is that when I'm waiting for them to fix it, there is a driveway entrance near work that has a pretty big dip, and if I accelerate out of it, the back end will drop just hard enough for the latch to engage, and the warnings will cease. You might be able to do the same with a speed bump. I've never had the hatch pop open during the time it's "partially" engaged.