Object required error with VBA rows deleting

The macro below should remove rows with text in column "A" containing "1" digit(e.g. A1, AB1) and rows below it, if cell in column "A" is empty and cell in column "K" is not empty. When there is a row with "1" and one row below it- macro removes this row below, then the error appears: "object required" and a row with "1" is not removed. When there are only rows with "1" without these rows below - it is ok, the rows are removed.
Someone helps?

Sub planp()
Dim n
Dim eCell
Dim eCell1
Dim eCell2

For n = 64 To 1 Step -1

Set eCell = Worksheets("Arkusz4").Cells(n, 1)
Set eCell1 = Worksheets("Arkusz4").Cells(n + 1, 1)
Set eCell2 = Worksheets("Arkusz4").Cells(n + 1, 11)

If Right(eCell.Value, 1) = "1" Then

Do While eCell1.Value = "" And eCell2.Value <> ""
Worksheets("Arkusz4").Rows(n + 1).Delete
Loop
Worksheets("Arkusz4").Rows.Delete
End If
Next
End Sub