I wanna ask "do loop" formula. The formula which i have used, But it still debug. Here is my formula :

Sub TEst()

Dim c As Range

Set c = Range("D4:D24")

Do Until c.Value = "21"

If c.Value <> 21 Then

c.EntireRow.Delete

End If

Loop

End Sub

so i want excel to delete entire row between D4:D24 if not meet the criteria, but if it meets with criteria excel will stop to search data. What's wrong with my formula?