Not getting parameter in Elementor Pro (fields are differen)

Using Elementor Pro and cannot get parameters to populate.

Only Custom ID is shown here:
https://handldigital.com/utm-grabber/documentation/public/books/elementor-integration/page/elementor-integration

I have tried using Custom ID as per document above. I have also tried adding eg ‘utm_campaign’ as default value (an extra option in Elementor Pro).

Neither work ??

If input as custom ID, it returns a blank value. I have checked cache etc via https://handldigital.com/utm-grabber/documentation/public/books/102-getting-started-for-handl-utm-grabber-v3/chapter/there-is-no-utm-collected troubleshooting.