PayPal Pro & Express Checkout is requiring API information when I click save, and the API setup in Paypal requires the "Third Party Permission Username." Where can I find this? It's supposed to be provided, as shown below, but I can't find it - Looking it up in Google, I find:
The third party requiring permission provides this username.
For example, the username for 3dcart is "paypal_api1.3dcart.com."