diff --git a/requirements.txt b/requirements.txt
old mode 100755
new mode 100644
index 4c70343..9616f3f
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,7 +1,7 @@
 # algorithms
 numpy==1.26.0
 pandas==2.1.1
-nltk==3.8.1
+nltk==3.9
 anytree==2.10.0
 networkx==3.1
 chardet==5.2.0