title: Grouping fields in Google Data Studio
body: <p>In Google Data Studio, I am trying to group different stages and assign them to a group for viewing in a sales funnel. The data are all strings. What I'm confused about is the fact that this data works just 1 or 2 weeks ago and the graph is already there. However, when I try to change the grouping, it shows the error "Invalid formula" or "Failed to create field. Please try again later"</p>
  
  <p>I have also tried to clone this code to create another field and it doesn't work at all. Have anyone encountered this problem and found a solution? </p>
  
  <p>Here is the associated code:</p>
  
  <pre><code>CASE
    WHEN Stage IN ("Interested", "Good Lead", "Good Leads") THEN "Prospected"
    WHEN Stage IN ("Attempted 1st", "Attempted 2nd") THEN "Attempted"
    WHEN Stage IN ("Contacted", "Lukewarm Lead", "Warm Lead", "Cold Lead", "Qualified Lead") THEN "Contacted"
    WHEN Stage IN ("Course Chosen") THEN "Docs Collection"
    WHEN Stage IN ("Document Collected", "School Applied") THEN "School Applied"
    WHEN Stage IN ("Paid") THEN "Paid"
    WHEN Stage IN ("Visa Applied") THEN "Visa Application"
    WHEN Stage IN ("Finished") THEN "Won"
    ELSE "0"
  END
  </code></pre>