Selections Plugin Configuration

I have a problem with configuration of dependent dropdowns (using observerId).
When I create document with dependent dropdowns and copy it something weird is happening. Dropdowns from copied doc observe dropdowns from original version. When I change value in dropdown then I have changes on original document also.
I searched the forum and couldn’t find a similar problem. Is there any way to fix that?

Have you prefixed observableId / observerId with


as described on:

Thank u for your response @machak !
Now I realized , I haven`t.
But when I add it (${}.<name_id>), fetching values to dropdown stopped working.
Maybe because dropdowns are in different compounds?
How to check the value of variable?