diff --git a/check_http_json.py b/check_http_json.py
index 05a65df..08df991 100755
--- a/check_http_json.py
+++ b/check_http_json.py
@@ -56,7 +56,7 @@ class NagiosHelper:
 	def append_critical(self, critical_message):
 		self.critical_message += critical_message
 	def append_unknown(self, unknown_message):
-		self.critical_message += critical_message
+		self.critical_message += unknown_message
 	def append_metrics(self, (performance_data, warning_message, critical_message)):
 		self.performance_data += performance_data
 		self.append_warning(warning_message)