Null pointer access - fix

Change-Id: I611727000bfcd15d36f3bed5a5d609031fcf791c
diff --git a/apps/openstackswitching/app/src/main/java/org/onosproject/openstackswitching/OpenstackSwitchingRulePopulator.java b/apps/openstackswitching/app/src/main/java/org/onosproject/openstackswitching/OpenstackSwitchingRulePopulator.java
index c765ef4..38c0363 100644
--- a/apps/openstackswitching/app/src/main/java/org/onosproject/openstackswitching/OpenstackSwitchingRulePopulator.java
+++ b/apps/openstackswitching/app/src/main/java/org/onosproject/openstackswitching/OpenstackSwitchingRulePopulator.java
@@ -163,7 +163,7 @@
                 .filter(n -> n.id().equals(port.networkId()))
                 .findAny().orElse(null);
         if (network == null) {
-            log.warn("No VNI information for network {}", network.id());
+            log.warn("No VNI information for network {}", port.networkId());
             return null;
         }