I am trying to connect to an affiliate site (Tapfilliate) so I can track purchases and reward my affiliates but I am stuck on how to assign my website's member IDs to the code. I have posted the code below, but I want to have a unique identifier so I can track which members have purchased. The field for the unique ID is 'external id'.
tap('conversion', 'external id', 299.99);
What can I change the 'external id' field to so it shows my website member's ID or email?
Thanks for your help.