title: Group by concatenate unique string only in Excel Pivot table or Power query
body: <p>I have table and output desired like this:
  <a href="https://i.stack.imgur.com/7OKwb.png" rel="nofollow noreferrer">I have tried the formula Concatnatex</a></p>
  
  <p>I had tried this function: =CONCATENATEX(Table1,[sender name]," , ") in Pivot table. But it also including duplicate value from sender name. Can we add distinct somehow in this formula?</p>
  
  <p>I want each value at to be considered once in concatenated column against the parent column.</p>
  
  <p>Thanks in advance.</p>
  
  <p>Kulchandra</p>