It takes 1-2 minutes to respond when changing a value of cell

[jayce_sos]

I have here a vba code for my excel. Primary function is to count number of days from a dates and return a number with conditional formatting of a cell. My problem is every time I change a value in a cell it take 2-3 minutes long to respond. I already tried the screenupdating function but with no luck same issue encountered. Below is the source code. Anyone knows how to fix this? Thank you in advance.

Private Sub Worksheet_Change(ByVal Target As Range)
Dim lngNumber As Long

On Error Resume Next
If Target.Address <> "I:J" Then
If Target.Count = 9 Then Exit Sub
If Target.Column = 9 Then
  Select Case UCase(Target.Value)
    Case "WL"
      lngNumber = 5
    Case "BL"
      lngNumber = 7
    Case "CIL", "SL", "TYL"
      lngNumber = 15
    Case "RAM", "CPR"
      lngNumber = 30
    Case Else
      lngNumber = 0
  End Select
End If
End If

If lngNumber < 31 Then
  Application.EnableEvents = False
  Target.Offset(0, 1).Value = lngNumber
  Application.EnableEvents = True
End If

If Target.Count = 1 Then
  If Not Intersect(Target, Range("H:J")) Is Nothing Then
    Application.EnableEvents = False
      Cells(Target.Row, "K").Value = Format(Cells(Target.Row, "H") + Cells(Target.Row, "J"), "MMM DD, YYYY")
    Application.EnableEvents = True
  End If
End If

If Target.Address <> "L:L" Then
If Target.Count = 1 Then
    Application.EnableEvents = False
    Cells(Target.Row, "L").Value = (Cells(Target.Row, "K") - (Now()) + 1)
    Application.EnableEvents = True
End If
End If

If Target.Address <> "M:H" Then
If Target.Count = 1 Then
      Application.EnableEvents = False
      Cells(Target.Row, "N").Value = Cells(Target.Row, "M") - Cells(Target.Row, "H")
      ActiveSheet.UsedRange.Columns("N").NumberFormat = "General"
      Application.EnableEvents = True
      
End If
End If
End Sub