diff --git a/README.md b/README.md
index fca13a9..fbfe91b 100644
--- a/README.md
+++ b/README.md
@@ -102,7 +102,7 @@ For sending messages with predefined pattern(e.g. verification codes, ...), you
 ```python
 pattern_variables = {
     "name": "string",
-    "code": "integer",
+    "code": ["integer", 10], # first element is type of variable and second one is length of this.
 }
 code = sms.create_pattern(r"%name% is awesome, your code is %code%", "description", pattern_variables, "%", False)
 
diff --git a/ippanel/client.py b/ippanel/client.py
index c4a431d..fb0f7b0 100644
--- a/ippanel/client.py
+++ b/ippanel/client.py
@@ -133,14 +133,14 @@ def create_pattern(self, pattern, description, variables, delimiter="%", is_shar
         :rtype: int
         """
         params = {
-            "pattern": pattern,
+            "message": pattern,
             "description": description,
             "delimiter": delimiter,
             "variable": [],
             "is_shared": is_shared,
         }
-        for variable_name, type in variables.items():
-            params['variable'].append({'name': variable_name, 'type': type})
+        for variable_name, type_len in variables.items():
+            params['variable'].append({'name': variable_name, 'type': type_len[0], 'len': type_len[1]})
 
         res = self.client.post("sms/pattern/normal/store", params)