Find and Replace ### ### with just ###

statejj16 

If you are okay with a vba suggestion, you could try this (change the range reference to whatever your actual range is). And, be sure to back up your data before trying to ensure it's what you're looking for.

Sub test()
     Dim cell As Range
     
     With CreateObject("VbScript.RegExp")
          .Pattern = "(\d{3}) \1"
     
          For Each cell In Range("A1:A100")
               If .test(cell.Value) Then
                    cell.Value = .Replace(cell.Value, "$1")
               End If
          Next cell
     End With
     
End Sub