diff --git a/bot bond sell.py b/bot bond sell.py
index d6e571d..5423dd2 100644
--- a/bot bond sell.py	
+++ b/bot bond sell.py	
@@ -203,14 +203,15 @@ class ExchangeConnection:
     ):
         """Add a new order"""
         self._write_message(
-            {
-                "type": "add",
-                "order_id": order_id,
-                "symbol": symbol,
-                "dir": dir,
-                "price": price,
-                "size": size,
-            }
+        {
+            "type": "add",
+            "order_id": order_id,
+            "symbol": symbol,
+            "dir": dir,
+            "price": price,
+            "size": size,
+            "tif" : "GFD",  # Good-For-Day (주문이 체결되거나 취소될 때까지 유효) 
+        }
         )
 
     def send_convert_message(self, order_id: int, symbol: str, dir: Dir, size: int):