Conditional Logic: Do not allow duplicate physical address - Unique question

id like to setup a form where people put their address to claim a free gift but only one address is allowed. 

I'm currently looking at your request, I'll update you on this same thread as soon as I have some news.

Hello,

Thank you for waiting, in this case, I found a way to achieve your request.

You can test the demo form here; https://form.jotform.com/200755749285970, feel free to clone it, guide How-to-Clone-an-Existing-Form-from-Your-Account.

As you can see at the following animation, the form is not going to accept a duplicate address:

1. Create a form with one Address and one Short Text Field (You can also hide the field to your users):

2. Now, go to Settings > Conditions > Select Update / Calculate Field > and select the following conditions.

Guide How-to-Pass-Field-Value-to-Another-Field.

3. In the last step, please go to Settings > Form Settings then under Unique Questions select the name of the Short Text field.

For more information about how to create a Unique Question, please visit the form here.

If you need any further assistance, please let us know. We will be happy to help.