The Second PIN (AKA Internet PIN or PIN 2) is only used for online purchases in Iran. This feature is something that is only available in Iran. So, you probably have not heard about this before!
When you make online purchases on Iranian websites, your second PIN is also needed to verify the transaction. Please note that your Second PIN is not included in your Card package for security porpuses.
To get your Second PIN you would need to visit the card issuing bank’s ATM. (your card’s issuing bank is Iranzamin Bank) and from the ATM machine’s menu choose to activate Second PIN and then you can set up your Second PIN there.