diff --git a/brewman/brewman/models/client.py b/brewman/brewman/models/client.py
index afa88caf..0eba5d6a 100644
--- a/brewman/brewman/models/client.py
+++ b/brewman/brewman/models/client.py
@@ -22,7 +22,7 @@ class Client(Base):
     code: int = Column("code", Integer, unique=True, nullable=False)
     name: str = Column("name", Unicode(255), unique=True, nullable=False)
     enabled: bool = Column("enabled", Boolean, nullable=False)
-    otp: int = Column("otp", Integer)
+    otp: Optional[int] = Column("otp", Integer)
     creation_date: datetime = Column("creation_date", DateTime(), nullable=False)
 
     login_history: List["LoginHistory"] = relationship(
@@ -34,7 +34,7 @@ class Client(Base):
         code: int,
         name: str,
         enabled: bool,
-        otp: int,
+        otp: Optional[int],
         creation_date: Optional[datetime] = None,
         id_: Optional[uuid.UUID] = None,
     ) -> None: