diff --git a/python_aternos/atclient.py b/python_aternos/atclient.py
index a07da0b..6835f49 100644
--- a/python_aternos/atclient.py
+++ b/python_aternos/atclient.py
@@ -92,7 +92,7 @@ class Client:
         self.atconn.generate_sec()
 
         credentials = {
-            'user': username,
+            'username': username,
             'password': md5,
         }