Hi Ana, the best place for this is probably a support request. You can create a ticket via support.mendix.com where you include the details of what you’ve found.
As a follow-up on this discussion, I’ve registered an Idea to have a Feedback button directly in the Academy courses so that any error, mistake, etc that is seen can be reported directly and on the spot.
Feel free to vote up the idea here: https://forum.mendix.com/link/ideas/2765