Discord won't let me accept an invite to a private server.

Hi folks-mainly posting this here because I really need the help and can't find a solution anywhere else so far.

So, anyway, I recently wanted to rejoin a Patreon-connected Discord server I'd been a part of since Nov. of '19 until last month.....but I ran into a big problem. I'd been having some issues with Patreon previously that I'm still largely sure have been sorted out(payment issues, I think), but even now, Discord keeps telling me I'm unable to join the server, even those the server's creator(who I'm still on good terms with!), kindly reached out to me and gave me a fresh new invite. Any ideas on what's causing this problem? Really am bummed that this is happening, TBH, as this was a community I enjoyed being a part of, and would love to rejoin when possible. =(