Envato Purchase code is very important for a customer to verify his purchase to the author. most of the author gonna ask you about purchase code when you go want to get support.
How to find your purchase code
Hover the mouse over your username at the top of the screen.
Click ‘Downloads’ from the drop-down menu.
Click ‘License certificate & purchase code’ (available as PDF or text file).
Step by Step Screenshort
Here is an example of License certificate & purchase code PDF