Cannot read property 'x' of undefined ts

Hi, I’m new here. The first, sorry for my english :smiley:

Well… I want to create a JSON object to call an api resource. I get all the vars from 3 forms and bind it to 3 variables.

Here the 3 console.log to each one when i click on “create client”

But when i try to create an object i get this error Cannot read property ‘fuente’ of undefined.
I need to create an object like this:

So i try this for example:

But i get this error:

I know that in view i should use: “{{ segmentacion.fuentes?.id }}” because DOM but i don’t know what is the problem here.

Thank you and again, sorry for my bad english.

You create Then you try to write stuff in But doesn’t exist yet, so it tells you exactly that.