diff --git a/fn.go b/fn.go
index 551c94c..eb28a85 100644
--- a/fn.go
+++ b/fn.go
@@ -141,14 +141,15 @@ func getSelectedEnvConfigs(in *v1beta1.Input, extraResources map[string][]resour
 		}
 		switch config.GetType() {
 		case v1beta1.EnvironmentSourceTypeReference:
+			envConfigName := config.Ref.Name
 			if len(resources) == 0 {
 				if in.Spec.Policy.IsResolutionPolicyOptional() {
 					continue
 				}
-				return nil, errors.Errorf("Required environment config %q not found", extraResName)
+				return nil, errors.Errorf("Required environment config %q not found", envConfigName)
 			}
 			if len(resources) > 1 {
-				return nil, errors.Errorf("expected exactly one extra resource %q, got %d", extraResName, len(resources))
+				return nil, errors.Errorf("expected exactly one extra resource %q, got %d", envConfigName, len(resources))
 			}
 			envConfigs = append(envConfigs, *resources[0].Resource)