Sage CRM 2023 R2

When configuring SageCRM emails with out Outlook M365 server, I keep getting the same error. The credentials have been entered correctly and our MSP says that it should work even witH SendAs disabled. Is this an OAuth issue?

>SMTP: Cannot use AUTH LOGIN. This may be caused by authentication not being enabled on the MTA, or an incorrect username / password. Retrying without authentication. Message: EIdSMTPReplyError: Authentication unsuccessful [SA9P221CA0004.NAMP221.PROD.OUTLOOK.COM 2026-02-26T17:15:08.919Z 08DE75140DD50DB6]

>SMTP: could not send email. Message: EIdSMTPReplyError: Client not authenticated to send mail. Error: 535 5.7.3 Authentication unsuccessful [SA9P221CA0004.NAMP221.PROD.OUTLOOK.COM 2026-02-26T17:15:13.962Z 08DE75140DD50DB6]