diff --git a/scripts/pi-hole/js/groups-common.js b/scripts/pi-hole/js/groups-common.js
index 99756901..005ce7d8 100644
--- a/scripts/pi-hole/js/groups-common.js
+++ b/scripts/pi-hole/js/groups-common.js
@@ -116,7 +116,7 @@ function validateIPv6CIDR(ip) {
       ipv6elem +
       "))*::((?:" +
       ipv6elem +
-      "))((?::" +
+      "))*((?::" +
       ipv6elem +
       "))*|((?:" +
       ipv6elem +