diff --git a/uc2rest/UC2Client.py b/uc2rest/UC2Client.py
index 88d7aee..4f3a32d 100644
--- a/uc2rest/UC2Client.py
+++ b/uc2rest/UC2Client.py
@@ -173,7 +173,7 @@ def post_json(self, path, payload, getReturn=True, nResponses=1, timeout=1):
         elif self.is_serial or self.isPyScript:
             if timeout <=0:
                 getReturn = False
-            return self.serial.post_json(path, payload, getReturn=getReturn, nResponses=nResponses, timeout=timeout)
+            return self.serial.post_json(path, payload, getReturn=getReturn, timeout=timeout, nResponses=nResponses)
         else:
             self.logger.error("No ESP32 device is connected - check IP or Serial port!")
             return None