conceptual mass desappears in cloud render

[rasha.qassem]

i'm doing an urban design project using links and some of the units contains conceptual massing that doesn't appear when i render in cloud tho it did at the beginning, the units are all linked to the file and i can't really put a wall by face because the mass contains some tight spots 

i've checked the visibility in the view settings but it didn't work 

my final submission is really soon please help, how can i make them appear again?

[Anonymous]

you have to check the material of the conceptual mass it might not have a material yet so it render as a void that is why it doesn't appear