I have the following models:

class BaseMessage(BaseModel):
    """
    Base schema for returning a ACK/NACK response.
    """

    origin: str = settings.APP_ORIGIN_NAME
    message: str

class Success(BaseMessage):
    """
    API schema for returning a Success response.
    """

    id: str
    temp_password: Optional[str] | None

class ACK(BaseModel):
    """
    API schema for returning an ACK response.
    """

    ACK: Success

and in my endpoint, I have this:

ack_message = ACK(
            message=success_text,
            id=domain_id,
            temp_password=instance.domain_hashed_password,
        )

return JSONResponse(
      status_code=status.HTTP_201_CREATED,
      content=jsonable_encoder(ack_message),
)

I keep getting an

ACK
  field required (type=value_error.missing)

message, which is not clear to me why as I am providing all the fields. Well at least I think I am.