How to control of repeating procedures? (delete duplicates rows)

I would like to create a structure for repeated operations by using Do While Loop. The DElDuplicates, which searches for and deletes duplicates rows in a database is a good example to explain the situation. Having sorted the database on a specific 'code' field, the entries in the code column are processed row-by row. If the values of the currentCell and nextCell are the same, the currentCell row is deleted.

I think my problem is caused by the reference objects. I don't know how to name it in my worksheet.

Sub DelDuplicates()
Dim currentCell, nextCell
Range("database").Sort key1:=Range("code") ----------- error here?
Set currentCell = Range("code")
Do While Not IsEmpty(currentCell)
  Set nextCell = currentCell.Offset(1, 0)
  If nextCell.Value = currentCell.Value Then
    currentCell.EntireRow.Delete
  End If
  Set currentCell = nextCell
Loop
End Sub

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