How to getValue from Related table's field

Hello guys,

Need some help for some JavaScript for I only know just a little bit about this. So in my Model-driven form, I have added field from Related Data - Quick View, Something like this ->

And then I created JavaScript to getValue from this field, by using code ->

    const formContext = executionContext.getFormContext();
    const formType = formContext.ui.getFormType();
    if (formType == 1) { // If Create
        return;
    }
    const isActive = formContext.getAttribute("jyp_active").getValue();

and put this script at OnLoad component of my form.

However I'm hit error like this :

What is the right syntax to get value of that field ? Or is there some differences when the field is coming from a Quick View from related table ?

Btw, please advice whether my question is not clear so I can add more information and make it more clearer. Sorry, because I'm new to this, not sure what I should explain further.

Thanks