Did you create your personal configuration? When you do, their server should be detecting the geolocation of your IP and assign the nearest ones (what you see a

Did you create your personal configuration? When you do, their server should be detecting the geolocation of your IP and assign the nearest ones (what you see at "DNS Servers") to that configuration like how CDN works. You can also check the assigned region at https://ipv4.dns.nextdns.io/ping https://ipv4.dns.nextdns.io/ping.