diff --git a/ucoin/hdc/__init__.py b/ucoin/hdc/__init__.py
index 20495986fdd8b50903fc7f9001b054a4c8c1d9cb..701e3513a1ac0165a5a3adc8e608e34edf9f2644 100644
--- a/ucoin/hdc/__init__.py
+++ b/ucoin/hdc/__init__.py
@@ -23,7 +23,7 @@ logger = logging.getLogger("ucoin/hdc")
 
 
 class HDC(API):
-    def __init__(self, server=None, port=None, module='hdc'):
-        super().__init__(module, server, port)
+    def __init__(self, module='hdc', server=None, port=None):
+        super().__init__(module=module, server=server, port=port)
 
 from . import amendments, coins, transactions