Can't delete names that are all numbers in userform listbox.

Hello all! In this macro I can't delete names that are all numbers via the userform. I can delete names that are mixes of letters and numbers just not all numbers (e.g 123123123). Any help on fixing this would be greatly appreciated! I am attaching the file for convenience.

The error in debug pinpoints the line that i am underlining in the following code.

Private Sub CommandButtonDeleteUpdate_Click()


'use RemoveItem method to delete a ListBox row. The below code deletes the row from the
'ListBox and also deletes the row items (or rows) in the worksheet
    Dim n As Long
    Dim k As Long
    Dim var As Variant


    'deleting row from ListBox using RemoveItem method:

    'check all items in a ListBox; reverse order (Step -1) is used because rows are being deleted from ListBox.
    For n = ListBoxDeletePickSiteList.ListCount - 1 To 0 Step -1

        If ListBoxDeletePickSiteList.Selected(n) = True Then

            'item to be deleted is stored in the variable named var
            var = ListBoxDeletePickSiteList.List(n, 0)
            ListBoxDeletePickSiteList.RemoveItem (n)


            'determine row number in which items are to be deleted; Note: value of variable named var
            'is derived from first column, hence Range("A:A") is searched in the Match formula.
            k = Application.Match(var, Worksheets("Site List").Range("B:B"), 0)

            'delete the row to the corresponding item in listbox
            Worksheets("Site List").Rows(k).Delete

            Exit For

        End If

    Next n

    'Refresh list
    LoadListBoxDeletePickSiteList
    LoadComboBoxEditSiteName

End Sub