still have empty cell after run Delete empty cells code

I have to run few time to delete all empty cell if Range A5:A20 are empty. Please help me

Dim lastrow As Long
Dim iCell As Long

lastrow = Range("A" & Rows.Count).End(xlUp).Row

For iCell = 1 To lastrow
    If Range("A" & iCell) = "" Then
        Range("A" & iCell).Delete Shift:=xlUp
    End If
Next iCell

Regards,
tt3