update fields in CRM

update fields in CRM

I'm doing the survey and CRM integration so that when the customer sends the survey, some fields are updated I have in my Invoice module.
That should take the CRM field to be updated?
I'm taking "Subject" but I do not update anything.

Could you please help me and give me the steps so that the fields are updated after the customer answers the survey.

In the subject field I have a parameter that is sent from a link that sends the customer to answer the survey.

I have a parameter in the "subject" field survey, which is sent from a link that sends the customer to answer the survey.