I didn't know which forum this should go into.

I have a 6x2 beech box for a vintage coticule. After using the coticule off and on for about an hour and a half (I was doing several razors at once) I realized the box had gotten really warped. So warped that the top won't go on it anymore. The bottom outside surface is now concave, the inside where the stone rests is convex.

Does anyone have any ideas about what to do with it? Is it possible to 'unwarp' wood?