See-Through exterior of Water Tower model

[1.dronemappingsoftware]

Hello.
This is the first time running Pix4Dmapper and I ran into a problem after doing a water tower project.
I cannot figure out why the walls of the water tower are see-through.

I am thinking it might have something to do with the contrast of the white, but the white buildings below are not having this problem.
I am also thinking it might have something to do with exposure, but not really sure about it.

Has anyone had this issue before and is there a way to fix it?

Thank you.

[Kapil_Khanal]

Hello @1.dronemappingsoftware, This has to do with the texture of the surface, the flight distance, and the number of images/overlap. If you fly too close to the tower, and due to the texture of the tower, it might be difficult to extract enough matched keypoints. Is this your densified point cloud? My suggestion would be to increase the overlap and be far from the tower while capturing the images.