Unable to send email with smtp.office365.com

Hello,

I have a process that has an email connector. In the email connector, my smtphost is a local exchange server where authentication is not required. The local exchange server accepts open relay. This configuration works. However, my organization is changing to Exchange Online where authentication is required. When I run my process, while connected to smtp.office365.com as the host server, I get the following error: Could not connect to SMTP host: smtp.office365.com, port: 25;. SSL is checked as the security. I've also tried where STARTTLS is checked. When testing where STARTLS is checked, I get the following error: TLS 1.0 and 1.1 are not supported. Please upgrade/update your client to support TLS 1.2. Visit https://aka.ms/smtp_auth_tls. [MN2PR06CA0015.namprd06.prod.outlook.com

Please advise on how I can fix this issue.