I’m trying to find a way to connect a list item to a Nintex live form item. I'm struggling to build a unique Nintex Live URL to include the item ID.

Context:

An internal user creates an item in the list

An external user receives a link to the Nintex live form (via a workflow that is started when the internal person creates and submits a list item)

When the external user completes and submits the Nintex live form, it creates a new item in the list. (Problem is: it needs to update an existing item that was created by the internal user – the item where the workflow is running).

How can I achieve this? If this is not possible, what would be an alternative solution to having both data from internal and external as 1 list item?