fixed bug with unique id creation during spreadsheet upload

backend/app/routers/dewar.py

@@ -50,7 +50,6 @@ def generate_unique_id(db: Session, length: int = 16) -> str:
 @router.post("/", response_model=DewarSchema, status_code=status.HTTP_201_CREATED)
 async def create_dewar(dewar: DewarCreate, db: Session = Depends(get_db)) -> DewarSchema:
     try:
-        unique_id = generate_unique_id(db)
         db_dewar = DewarModel(
             dewar_name=dewar.dewar_name,
             tracking_number=dewar.tracking_number,
@@ -61,7 +60,6 @@ async def create_dewar(dewar: DewarCreate, db: Session = Depends(get_db)) -> Dew
             returning_date=dewar.returning_date,
             contact_person_id=dewar.contact_person_id,
             return_address_id=dewar.return_address_id,
-            unique_id=unique_id
         )
         db.add(db_dewar)
         db.commit()
@@ -105,7 +103,7 @@ async def generate_dewar_qrcode(dewar_id: int, db: Session = Depends(get_db)):
         raise HTTPException(status_code=404, detail="Dewar not found")
 
     if not dewar.unique_id:
-        dewar.unique_id = generate_unique_id(db)
+        raise HTTPException(status_code=400, detail="Unique ID must be set during label creation.")
 
     qr = qrcode.QRCode(version=1, box_size=10, border=5)
     qr.add_data(dewar.unique_id)