Hey, man, perhaps you're using a timed Discord invite?
I tried the one in this page, in the wiki, at f95zone and SubscribeStar but none of them seem to be working :v
Nope, the link doesn't have set an expiration date
You might try the alternative one
but I'm quite sure that the outcome will be the same...
The problem, I'm afraid, lies on your end - try googling / asking AI for potential solutions and be sure to include "the discord invite link has no expiration date set and it works for others but not for me" or sth along those lines