title: Failed to create field. Please try again later: Google Data Studio
body: <p>I am trying to count the occurrence of an event on Google Data Studio (via a BigQuery Connector), however, even for a correct formula "<em>Please try again later appears</em>". The error sometimes to invalid formula.</p>
  
  <p>I have tried refreshing the data source and yet there is no luck.</p>
  
  <p>Here is the query:</p>
  
  <pre><code>SUM(CASE
      WHEN event_name = 'Cashin' THEN 1
      ELSE 0 END)
  </code></pre>