Connecting Javascript with hubspot form - query string methodolgy does not work



I want to make when client input their numbers in to calculator(left side of the page) and when the results come out(red dot on the right side), automatically records goes in to budget(below form) field.
FYI, red dot section is made of Javascript. Hubspot support service gave us the information about query string of the url but it does not work.

How can I automatically attach red dot figures to budget field?


Welcome, @nikkiminki!

The only way I know how to do this would be to populate the calculated budget in the budget query string. See below and this Stack Overflow article:

What about this is not working?