I was told (via the Discord) to post this query here. I am suffering the error that won't let me connect. See attached image.

I have tried everything I can think of, including what little I could find in the discord server. I've verified the game installation, deleted and reinstalled it, checked Steam for updates, checked my firewall, restarted my system multiple times, reset my router, flushed my DNS and reset my IP, performed a Windows Network Reset. Nothing has worked.
Invitations from friends pop up, but I cannot accept them, nor can I invite them or queue for matches without the error appearing.
Is there a known fix for this? I am EU region if that helps. Thanks in advance.

I have tried everything I can think of, including what little I could find in the discord server. I've verified the game installation, deleted and reinstalled it, checked Steam for updates, checked my firewall, restarted my system multiple times, reset my router, flushed my DNS and reset my IP, performed a Windows Network Reset. Nothing has worked.
Invitations from friends pop up, but I cannot accept them, nor can I invite them or queue for matches without the error appearing.
Is there a known fix for this? I am EU region if that helps. Thanks in advance.