Heightmap feature no longer functioning

I have been trying to use heightmap to create alphas but recently the feature has stopped functioning altogether—the mesh is not visible even if I transform its position or change its scale, change the render focus, or tap on different points of elevation on the mesh. The same issue occurred on another device. Previously when I would use height-map, the mesh would show immediately almost all of the time, but in the past few weeks it has not worked at all. Please let me know how to fix this. Thank you.

Turn on post process - tone mapping. It is fixed in next Version - Web Demo works.

It worked, thank you so much!