Why is my mesh flipping? (Rigid body simulation) I'm attempting to run a simple rigid body simulation with the following parameters: A plane as a "floor" set as a passive rigid body, and a mesh "scrabble tile" as an active rigid body and all defaults except for "Box" as the collision shape.

I'd like the scrabble tile to start face up, fall, and settle on the ground. The problem is that at frame 2, the mesh seems to completely flip so that the bottom side of the tile is facing up, for no apparent reason. See screenshots (can't post a 3rd, but if you rotate underneath the tile in frame 2, you'd see the text).

Any advice on fixing this would be greatly appreciated. Thanks!

Here is frame 1 (good):


Here is frame 2 (bad):
I had the same problem in blender 3.0, the cause was the object having a negative scale. It worked fine after updating the object's scale with positive values.
This link posted in one of the previous answers was useful:

https://blenderartists.org/forum/showthread.php?311350-Rigid-Body-Tools-turns-my-object-upside-down.