diff --git a/README.md b/README.md
index ccdbd37a..4d856c2c 100644
--- a/README.md
+++ b/README.md
@@ -1,13 +1,12 @@
 # IQ Option API
 
-last Version:3.6.2
+last Version:3.6.3
 
+last update:2019/4/2 
 
-last update:2019/3/21
+version 3.6.3
 
-version 3.6.2
-
-fix buy digit
+fix https://github.com/Lu-Yi-Hsun/iqoptionapi/issues/14#issuecomment-478817517
 
 ---
 ## About API
diff --git a/iqoptionapi/stable_api.py b/iqoptionapi/stable_api.py
index c9315412..44a436cd 100644
--- a/iqoptionapi/stable_api.py
+++ b/iqoptionapi/stable_api.py
@@ -562,7 +562,8 @@ def get_optioninfo(self, limit):
 # __________________FOR OPTION____________________________
 
     def buy(self, price, ACTIVES, ACTION, expirations, force_buy=False):
-        self.api.buy_successful == None
+        self.api.buy_successful = None
+        self.api.buy_id = None
         while True:
             while True:
                 try:
diff --git a/setup.py b/setup.py
index 0012bb07..c45e0592 100644
--- a/setup.py
+++ b/setup.py
@@ -3,7 +3,7 @@
 
 setup(
     name="iqoptionapi",
-    version="3.6.2",
+    version="3.6.3",
     packages=find_packages(),
     install_requires=["pylint","requests","websocket-client==0.47"],
     include_package_data = True,