Then it's a Discord bug ig. I also tried putting it to never expire and it really expired lol. Try an invite that expires in 7 days to see if it works.
From what I remember, Discord invites takes 15 or 30 mins to expire, but there is a way to make it work permanently, but I don't know how.
Can you please give another invite to the Discord server? The link on the main page is expired.
