diff --git a/.github/workflows/markdownlint.yml b/.github/workflows/markdownlint.yml
index da8a9a641..d7dd798e9 100644
--- a/.github/workflows/markdownlint.yml
+++ b/.github/workflows/markdownlint.yml
@@ -28,7 +28,7 @@ jobs:
         with:
           fetch-depth: 0
 
-      - uses: DavidAnson/markdownlint-cli2-action@v23
+      - uses: DavidAnson/markdownlint-cli2-action@v23.1.0
         with:
           globs: |
             **/*.md
diff --git a/pythainlp/soundex/sound.py b/pythainlp/soundex/sound.py
index 450968d1f..42010fd58 100644
--- a/pythainlp/soundex/sound.py
+++ b/pythainlp/soundex/sound.py
@@ -28,7 +28,6 @@ def _clean_ipa(ipa: str) -> str:
         .replace("˨˩", "")
         .replace("˦˥", "")
         .replace("˧", "")
-        .replace("˧", "")
         .replace(" .", ".")
         .replace(". ", ".")
         .strip()