diff --git a/requirements.txt b/requirements.txt
index 17f0af7..df9eb3e 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -78,6 +78,7 @@ pyhanko==0.21.0
 pyhanko-certvalidator==0.26.3
 pyjwt==2.8.0
 pymongo==4.6.1
+pyotp==2.9.0
 pypdf==4.0.2
 pypng==0.20220715.0
 python-bidi==0.4.2