diff --git a/backend/src/appointment/database/schemas.py b/backend/src/appointment/database/schemas.py
index 9885e0b5..d1ad2089 100644
--- a/backend/src/appointment/database/schemas.py
+++ b/backend/src/appointment/database/schemas.py
@@ -30,7 +30,7 @@
 class AttendeeBase(BaseModel):
     email: str
     name: str | None = None
-    timezone: str
+    timezone: str | None = None
 
 
 class Attendee(AttendeeBase):