diff --git a/plugins/wireguard/wireguard_ b/plugins/wireguard/wireguard_
index 46930769..a189e12b 100755
--- a/plugins/wireguard/wireguard_
+++ b/plugins/wireguard/wireguard_
@@ -94,6 +94,7 @@ function wg_interfaces {
         _wg_ifaces+=("$iface")
     done
 }
+
 declare -A _CACHE_PEERS
 function wg_peers {
     local -n _wg_peers=$1
@@ -165,8 +166,7 @@ EOF
 }
 
 function peer_traffic {
-    iface="$1"
-
+    local iface="$1"
 
     echo "multigraph wireguard_peertraffic_$iface"