Hello Kuntesh
I have already responded to you on the ticket, however I would like to do it here as well for anyone else asking this question to see what this could possibly be caused by. The issue here could be that when you are creating a custom module you need to make sure you set the UI elements for the custom module or else the settings will not display at all. There are two ways to do this, using the portal engine or defining them manually in code.
To manually create the UI elements in code you can follow this documentation:
https://docs.kentico.com/display/K82/Manually+creating+the+interface+for+custom+modules
If you are going to set them up using portal engine ( in Kentico UI ) then you can follow this documentation:
https://docs.kentico.com/display/K82/Creating+custom+modules#Creatingcustommodules-Buildingthemoduleinterface
Hope this helps!