diff --git a/network/manifests/init.pp b/network/manifests/init.pp
index b906d72..4df59fb 100644
--- a/network/manifests/init.pp
+++ b/network/manifests/init.pp
@@ -686,7 +686,7 @@ define network::routeradvertisement::ipv6prefix(
             }
         }
         default: {
-            fail("Router advertisement not supported in $::{operatingsystem}")
+            fail("Router advertisement not supported in ${::operatingsystem}")
         }
     }