I am using ABAP environment on BTP to send email via SMTP and I have configured the mail server successfully by creating a Communication system with server and port - smtp.office365.com / 587. I have also assigned an authentication with a new user and password.
The communication arrangement scenario used for mail is SAP_COM_0548.
In order to send the email I am making use of the released API class "CL_BCS_MAIL*" following this guide Sending Mails Using SMTP | SAP Help Portal
Unfortunately, mail is not getting sent and while executing the Class method CL_BCS_MAIL_MESSAGE->SEND, I retrieve the error message from debug as - 535 5.7.3 Authentication unsuccessful [FR3P281CA01
Any help will be appreciated.