diff --git a/ipv6/ar.cidr b/ipv6/ar.cidr
index d33616255..91de390e0 100644
--- a/ipv6/ar.cidr
+++ b/ipv6/ar.cidr
@@ -524,7 +524,6 @@
 2803:5ca0::/32
 2803:5ce0::/32
 2803:5d10::/32
-2803:5dc0::/32
 2803:5de0::/32
 2803:5e80::/32
 2803:5f10::/32
diff --git a/ipv6/gt.cidr b/ipv6/gt.cidr
index dc43154fd..71cee1cdf 100644
--- a/ipv6/gt.cidr
+++ b/ipv6/gt.cidr
@@ -9,6 +9,7 @@
 2801:17:c800::/48
 2801:18:b800::/48
 2801:1a:8800::/48
+2801:1c:8400::/48
 2801:1d:2000::/48
 2801:155::/40
 2801:1a5::/44