[VBA] unable to open Outlook (office 365)

[KirovHC]

Hello,
what's wrong with my code?

Dim oOutlook As Object
On Error Resume Next
    Set oOutlook = GetObject(, "Outlook.Application")
    On Error GoTo 0

    If oOutlook Is Nothing Then
        Set oOutlook = CreateObject("Outlook.Application")
    End If

If I try to send it with envelope method it appears on try that outlook it is being used by another program and the message remains in the outbox