diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 17fcafcc8..cc7e55cfe 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -2,8 +2,6 @@ name: Unit test and code coverage
 
 on:
   push:
-    branches:
-      - dev
     paths-ignore:
       - '**.md'
       - 'docs/**'
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 693f73400..fa384edd0 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -108,10 +108,10 @@ Make sure the same tests pass on Travis CI and AppVeyor.
   #current_version = 2.3.6-dev0
 
   bumpversion minor
-  #current_version = 2.3.0-dev0
+  #current_version = 2.3.1-dev0
 
   bumpversion build
-  #current_version = 2.3.0-dev1
+  #current_version = 2.3.1-dev1
 
   bumpversion major
   #current_version = 3.0.0-dev0
diff --git a/README.md b/README.md
index dfac9774e..fa54ac344 100644
--- a/README.md
+++ b/README.md
@@ -23,8 +23,8 @@ PyThaiNLP เป็นไลบารีภาษาไพทอนสำหร
 
 | Version | Description | Status |
 |:------:|:--:|:------:|
-| [2.3.0](https://github.com/PyThaiNLP/pythainlp/releases) | Stable | [Change Log](https://github.com/PyThaiNLP/pythainlp/issues/445) |
-| [`dev`](https://github.com/PyThaiNLP/pythainlp/tree/dev) | Release Candidate for 2.4  | [Change Log](https://github.com/PyThaiNLP/pythainlp/issues/445) |
+| [2.3.1](https://github.com/PyThaiNLP/pythainlp/releases) | Stable | [Change Log](https://github.com/PyThaiNLP/pythainlp/issues/445) |
+| [`dev`](https://github.com/PyThaiNLP/pythainlp/tree/dev) | Release Candidate for 2.4  | [Change Log](https://github.com/PyThaiNLP/pythainlp/issues/545) |
 
 
 ## Getting Started
diff --git a/README_TH.md b/README_TH.md
index e7a4761fe..facc5d699 100644
--- a/README_TH.md
+++ b/README_TH.md
@@ -22,8 +22,8 @@ PyThaiNLP เป็นไลบารีภาษาไพทอนสำหร
 
 | รุ่น | คำอธิบาย | สถานะ |
 |:------:|:--:|:------:|
-| [2.3.0](https://github.com/PyThaiNLP/pythainlp/releases) | Stable | [Change Log](https://github.com/PyThaiNLP/pythainlp/issues/445) |
-| [`dev`](https://github.com/PyThaiNLP/pythainlp/tree/dev) | Release Candidate for 2.4  | [Change Log](https://github.com/PyThaiNLP/pythainlp/issues/445) |
+| [2.3.1](https://github.com/PyThaiNLP/pythainlp/releases) | Stable | [Change Log](https://github.com/PyThaiNLP/pythainlp/issues/445) |
+| [`dev`](https://github.com/PyThaiNLP/pythainlp/tree/dev) | Release Candidate for 2.4  | [Change Log](https://github.com/PyThaiNLP/pythainlp/issues/545) |
 
 ติดตามพวกเราบน [PyThaiNLP Facebook page](https://www.facebook.com/pythainlp/) เพื่อรับข่าวสารเพิ่มเติม
 
diff --git a/pythainlp/__init__.py b/pythainlp/__init__.py
index 2a469d7e4..006d48d03 100644
--- a/pythainlp/__init__.py
+++ b/pythainlp/__init__.py
@@ -1,5 +1,5 @@
 # -*- coding: utf-8 -*-
-__version__ = "2.3.0"
+__version__ = "2.3.1"
 
 thai_consonants = "กขฃคฅฆงจฉชซฌญฎฏฐฑฒณดตถทธนบปผฝพฟภมยรลวศษสหฬอฮ"  # 44 chars
 
diff --git a/pythainlp/word_vector/core.py b/pythainlp/word_vector/core.py
index 67ef0f4d2..14898c817 100644
--- a/pythainlp/word_vector/core.py
+++ b/pythainlp/word_vector/core.py
@@ -257,7 +257,7 @@ def sentence_vectorizer(text: str, use_mean: bool = True) -> ndarray:
         elif word == "\n":
             word = _TK_EOL
 
-        if word in _MODEL.index2word:
+        if word in _MODEL.index_to_key:
             vec += _MODEL.word_vec(word)
 
     if use_mean:
diff --git a/setup.cfg b/setup.cfg
index 2cb9f7c28..a5d93ca4b 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,5 +1,5 @@
 [bumpversion]
-current_version = 2.3.0
+current_version = 2.3.1
 commit = True
 tag = True
 parse = (?P<major>\d+)\.(?P<minor>\d+)\.(?P<patch>\d+)(\-(?P<release>[a-z]+)(?P<build>\d+))?
diff --git a/setup.py b/setup.py
index 59eab3c16..d1d9d3336 100644
--- a/setup.py
+++ b/setup.py
@@ -79,7 +79,7 @@
 
 setup(
     name="pythainlp",
-    version="2.3.0",
+    version="2.3.1",
     description="Thai Natural Language Processing library",
     long_description=readme,
     long_description_content_type="text/markdown",