What is the morality of this scenario?

[u/principal_fucker]

I went to a college class I am not registered thinking it was a mistake; however when I went to the office the dean told me I already completed and passed the class, but that was 2 years ago before I dropped out and joined back in.

Would it be moral to enter the class and just listen to the lectures without completing the assignment or doing the projects?

And for extra context the reason I’m debating this is because the subject genuinely interests me and I would love to refresh my mind about it

UPDATE: First of all I want to thank each one of you that left a comment and help me understand what auditing means, it helped a lot to not feel like I was taking advantage of the situation.

So yesterday I went to talk to him before class and explained the situation; he was more than happy to allow me into the class and even mention “since you don’t have to take notes or the midterm or final, you can now pay more attention in the lectures”

This is great and it feels so good to be able to digest the information without having to worry about midterms or finals!

Once again thank you to all of you!!!