Excel vba对象变量或With块变量未设置错误

我在excel vba中进行编码，并且在运行代码时得到错误91或对象变量或With块变量未设置错误，我不确定为什么。我定义并设置了变量，所以我不知道是什么导致了错误。相关代码如下

  Sub Button5_Click()
Dim i As Integer
Dim Month As Range
Dim Avg As Range
Dim Target As Range
Dim Incorrect As Range

Set Month = Range("J19")
Set Avg = Range("H19")
Set Incorrect = Range("A19")
Set Target = Range("M19")

'Range("A" & Rows.Count).End(xlUp).Row
For i = 0 To 1000
If IsEmpty(Avg) Then

If Month.Find("jan") <> "" Then
Set Target = Range("M19")

错误出现在If Month.Find（“ jan”）<>“”的部分代码上。

完整的代码在这里：

Sub Button5_Click()
Dim i As Integer
Dim Month As Range
Dim Avg As Range
Dim Target As Range
Dim Incorrect As Range

Set Month = Range("J19")
Set Avg = Range("H19")
Set Incorrect = Range("A19")
Set Target = Range("M19")

'Range("A" & Rows.Count).End(xlUp).Row
For i = 0 To 1000
If IsEmpty(Avg) Then

If Month.Find("jan") <> "" Then
Set Target = Range("M19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("feb") <> "" Then
Set Target = Range("O19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("mar") <> "" Then
Set Target = Range("Q19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("apr") <> "" Then
Set Target = Range("S19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("may") <> "" Then
Set Target = Range("U19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("jun") <> "" Then
Set Target = Range("W19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("jul") <> "" Then
Set Target = Range("Y19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("aug") <> "" Then
Set Target = Range("AA19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("sep") <> "" Then
Set Target = Range("AC19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("oct") <> "" Then
Set Target = Range("AE19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("nov") <> "" Then
Set Target = Range("AG19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

Else
Set Target = Range("AI19")

If IsEmpty(Target) Then
Incorrect.Value = "X"

End If
End If

Else
If Month.Find("jan") <> "" Then
Set Target = Range("N19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("feb") <> "" Then
Set Target = Range("P19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("mar") <> "" Then
Set Target = Range("R19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("apr") <> "" Then
Set Target = Range("T19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("may") <> "" Then
Set Target = Range("V19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("jun") <> "" Then
Set Target = Range("X19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("jul") <> "" Then
Set Target = Range("Z19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("aug") <> "" Then
Set Target = Range("AB19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("sep") <> "" Then
Set Target = Range("AD19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("oct") <> "" Then
Set Target = Range("AF19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

ElseIf Month.Find("nov") <> "" Then
Set Target = Range("AH19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If

Else
Set Target = Range("AJ19")

If IsEmpty(Target) Then
Incorrect.Value = "X"
End If
End If
End If
Set Month = Month.Offset(1, 0)
Set Incorrect = Incorrect.Offset(1, 0)
Set Avg = Avg.Offset(1, 0)
Set Target = Target.Offset(1, 0)

Next i
End Sub

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