diff --git a/backend/app/models/user.py b/backend/app/models/user.py
index 4ec9c20..9abc1c7 100644
--- a/backend/app/models/user.py
+++ b/backend/app/models/user.py
@@ -18,7 +18,7 @@ class User(Base):
     email: Mapped[str] = mapped_column(String(255), unique=True, nullable=False, index=True)
     hashed_password: Mapped[str] = mapped_column(String(255), nullable=False)
     display_name: Mapped[str | None] = mapped_column(String(100))
-    role: Mapped[UserRole] = mapped_column(Enum(UserRole), default=UserRole.PENDING, nullable=False)
+    role: Mapped[UserRole] = mapped_column(Enum(UserRole, values_callable=lambda x: [e.value for e in x]), default=UserRole.PENDING, nullable=False)
     is_active: Mapped[bool] = mapped_column(Boolean, default=True, nullable=False)
     created_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow, nullable=False)
     updated_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow, nullable=False)