Lack of Block Physics on Server

[DoctorDDub]

I'm currently experiencing zero block physics on a dedicated server I'm hosting. I've tried using the command "/worldconfig blockGravity sandgravelsoil", restarting my server, and still, neither sand, gravel, nor soil have block physics. 

Does anyone know what I might be doing wrong or how to fix this?

[Seth Konkol]

I have this issue as well