How to select cesium entity which is under another cesium entity?

Hello Team,
I got stuck in one of tricky problem of selecting cesium entity based on mouse click.
The problem is I am not able to select the cesium entity which are under other cesium entity.
considering this diagram,
yellow is the polygon and red is sphere.
polygon is on the top and sphere is below polygon.
for some reasons I need to select sphere on mouse click, but since it is under the polygon I am not able to select it.

Any possible Idea or solution that I can implement to get my problem resolve ?

Thank you !!