VBA for auto sending email notifications.

[DPFIN]

Hello.

I searched the forum for VBA code to auto-send emails in outlook, and came up with the following, which I adjusted a little.

But would appreciate adjustments to fit my requirements if anyone can help. Any adjustments I tried resulted in errors or incorrect results.

Changes I would like(underlined);
1. If a number in a cell in N column changes to greater than 20%, or less than -20% an email is automatically sent.

2. Only one email per cell/row in each day 21:00 to 21:00.
(cells are auto-updated every 5 or so minutes. I only want a maximum of one email on the first breach of the +/- 20% threshold in each cell each day).

3. The email subject, and Body include the words from Column D and E, and the figure from Column N, from the same row as the trigger cell(N).
(These cells contain a category name(D), title(E), and the % number(N). )

Private Sub Worksheet_Change(ByVal Target As Range)    
    Dim rng As Range
    On Error Resume Next
    For Each rng In Intersect(Target, Range("N1:N500")).Cells
        If rng.Value > 20 Then
            With CreateObject("Outlook.Application").CreateItem(0)
                .To = "me@yahoo.com"
                .Subject = "Threshold Exceeded."
                .Body = "Message"
                .Send
            End With
        End If
    Next
    On Error GoTo 0
    
End Sub

Thank you in advance.