diff --git a/requirements.txt b/requirements.txt
index 56fd8aa..da99202 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -21,4 +21,5 @@ Pillow==9.1.0
 PDFNetPython3==9.1.0
 pdf2image==1.16.0
 frozendict==2.3.0
-prometheus-client==0.13.1
\ No newline at end of file
+protobuf<=3.20.*
+prometheus-client==0.13.1