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.
60a74708e09ebfac4d6a0ece01462012

Here the 3 console.log to each one when i click on “create client”
578384b53770f95084c48c5148654205
abf3a0c450db6e647c8995dbc6b44377

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:
https://gyazo.com/cba4b62ef061d82a96a830797e85c87c

So i try this for example:
https://gyazo.com/136650072388219c9c01482c5cdf007a

But i get this error:
https://gyazo.com/5e4c7601c60029244048ecda297a7963

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 this.post. Then you try to write stuff in this.post.segmentacion.fuente. But this.post.segmentacion doesn’t exist yet, so it tells you exactly that.