title: FastApi returns "field required" and "value_error.missing" for one of my parameters, but the field is there
body: <p>I do a Post with some parameters, but one of them returns &quot;field required&quot; and &quot;value_error.missing&quot;, but the field is there and it has a value. See the output of Postman.
  <a href="https://i.stack.imgur.com/20WqG.png" rel="noreferrer"><img src="https://i.stack.imgur.com/20WqG.png" alt="field &quot;body&quot; is not missing" /></a></p>
  <p>In schemas.py the fields are defined as follows:</p>
  <pre><code>class Message(BaseModel):
      title: str
      id: int
      datim: Optional[datetime]
      to_id: Optional[int]
      from_id: Optional[int]
      body: Optional[str]
  
      class Config:
          orm_mode = True
  </code></pre>
  <p>So why does it complain about 'body'?</p>