diff --git a/prepro/requirements.txt b/prepro/requirements.txt
old mode 100755
new mode 100644
index adc1d46..27edb39
--- a/prepro/requirements.txt
+++ b/prepro/requirements.txt
@@ -86,7 +86,7 @@ ssh-import-id==5.7
 system-service==0.3
 systemd-python==234
 tensorboard==1.12.0
-tensorflow==1.12.0
+tensorflow==2.6.4
 termcolor==1.1.0
 testresources==2.0.1
 twitter==1.18.0