This worked for me. I found that I changed my DNS server to Cloudflare with the AdGuard software installed on MacOS a while back (AdGuard > Preferences > DNS), and changing this to a different server fixed it.
I also used the command `sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder` on Terminal (double-check this command before using) to flush the DNS cache, so the change would immediately take effect with the archive websites.
The technical reasons behind it are that the archive.today guy wants any takedown notices to be cross-border, so he wants to know what country you are in so he can redirect you to a server outside it.
Cloudflare doesn't support a DNS extension that allows this (eDNS maybe?) and so it fails.