title: Microsoft Graph HonorNonIndexedQueriesWarningMayFailRandomly Error when filtering SharePoint Online lists
body: <p>I'm using ms-graph with SharePoint Online.
  I've a simple list with a single title column and 3 items.</p>
  
  <p>I use the following ms-graph call to filter items by title:</p>
  
  <p><a href="https://graph.microsoft.com/v1.0/sites/root:/lists/list-guid/items?expand=fields&amp;filter=startswith(fields/Title,%27fig%27)" rel="nofollow noreferrer">https://graph.microsoft.com/v1.0/sites/root:/lists/list-guid/items?expand=fields&amp;filter=startswith(fields/Title,%27fig%27)</a></p>
  
  <p>The result is an error message:</p>
  
  <blockquote>
    <p>Field 'Title' cannot be referenced in filter or orderby as it is not indexed. Provide the 'Prefer: <strong>HonorNonIndexedQueriesWarningMayFailRandomly</strong>' header to allow this, but be warned that such queries may fail on large lists.</p>
  </blockquote>
  
  <p>I know that this call was working before and also when I use SharePoint REST API then I can filter the list without any problems. I also tried different tenants.
  Another fact is that the same call is working without the startswith filter.</p>
  
  <p>Few days ago I had a different message for the same call.</p>
  
  <blockquote>
    <p>"Field 'Title' cannot be referenced in filter or orderby as it is not indexed. Provide the '<strong>allowthrottleablequeries</strong>' preference to allow this, but be warned that such queries may fail on large lists."</p>
  </blockquote>