Thymeleaf modal Variable in form action

Question

I'm using the following code,

    modalAndView.addObject("country", countryFetchByIdResponseDto);
    modalAndView.addObject("SERVICE_RESPONSE", countryFetchByIdResponseDto);
    modalAndView.addObject("BACK_BUTTON_LINK", "/fetchCountrybyPage?pageNumber=1&itemsPerPage=10");
    modalAndView.setViewName("PARENT_INGESTION_FORM");
    modalAndView.addObject("CHILD_FORM", "CountryIngestionView");
    modalAndView.addObject("PAGE_TITLE", "COUNTRY_FIND_BY_ID_PAGE_TITLE");
    modalAndView.addObject("PAGE_FUNCTIONAL_TITLE", "COUNTRY_FETCH_BY_ID_FUNCTIONAL_TITLE");
    modalAndView.addObject("FORM_ACTION", "/updateCountry");

The above form tag is in child page, all the modal variables are replaced but the action is not replaced.

Any mistakes in the approach?