How to identify which form this new form was the additional submission of without adding their name again?

and to know which form this new form was the additional submission of without adding their name again

Hi cc00, 

Thanks for reaching out to Jotform Support. I’ll need a bit of time to look into this. I’ll get back to you as soon as I can.

We appreciate your patience while we work on a solution.

Hi cc00,

Unfortunately, it is not possible to identify the submitter of the new form without adding their name. As a workaround, you can prefill the name field on the new form using URL Parameters. You can then appy a condition that if this product was selected they will be redirected to the new form. Let me show you how:

1. First, you need to create a URL Parameter to prefill your new form. You can use the URL parameter below, just edit the Form ID.

https://form.jotform.com/YourNewFormID?name[first]={name:first}&name[last]={name:last}

2. In Form Builder, click on Settings on the orange navigation bar on top of the page.

3. Click on Conditions on the left side panel, then click Add Condition.

4. Select Change Thank You Page.

5. Copy the Condition below then click Save.

See screencast below for the result:

Here's my demo form that you can clone for your reference.

Give it a try and let us know how it goes.