diff --git a/domain/entity/shift_position.py b/domain/entity/shift_position.py
index 435c850d..ee41a167 100644
--- a/domain/entity/shift_position.py
+++ b/domain/entity/shift_position.py
@@ -17,4 +17,5 @@ class ShiftPosition(Base):
     role = relationship("Role")
 
     # One-to-one relationship with ShiftRequestVolunteer using backref
-    volunteer = relationship("ShiftRequestVolunteer", uselist=False, backref="shift_position")
\ No newline at end of file
+    volunteer = relationship("ShiftRequestVolunteer", uselist=False, backref="shift_position",
+                             primaryjoin="ShiftPosition.id == ShiftRequestVolunteer.position_id")
diff --git a/domain/entity/shift_request_volunteer.py b/domain/entity/shift_request_volunteer.py
index b73447f0..93f2de9b 100644
--- a/domain/entity/shift_request_volunteer.py
+++ b/domain/entity/shift_request_volunteer.py
@@ -13,7 +13,7 @@ class ShiftRequestVolunteer(Base):
     id = Column(Integer, primary_key=True, autoincrement=True)
     user_id = Column(Integer, ForeignKey('user.id'), name='user_id', nullable=False)
     request_id = Column(Integer, ForeignKey('shift_request.id'), name='request_id', nullable=False)
-    position_id = Column(Integer, ForeignKey('role.id'), name="role_id", nullable=False)
+    position_id = Column(Integer, ForeignKey('shift_position.id'), name="position_id", nullable=False)
     status = Column(Enum(ShiftVolunteerStatus), name='status', nullable=False, default=ShiftVolunteerStatus.PENDING)
     update_date_time = Column(DateTime, name='last_update_datetime', default=datetime.now(), nullable=False)
     insert_date_time = Column(DateTime, name='created_datetime', default=datetime.now(), nullable=False)