Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
The web page seems to working properly now:
https://www.microsoft.com/en-us/home-use-program/order-history
EDIT: If someone is seeing this thread later than 2020, the link to the order history is new:
https://www.microsoft.com/en-us/workplace-discount-program/order-history