Send Mail (SMTP) through Office 365 with MFA

We have a web server that needs to be able to send emails as users (FROM field); however, we have noticed that if the user account is protected with MFA, the message is rejected.  Has anyone been able to get this working? I found a work around by using an account that does not have MFA then adding that account as a delegate of the sending user, but that seems a bit extensive. 

 

In our scenario, web server sends a message showing it comes from a sales rep, that is populated dynamically on the web server. It uses CFMAIL (same rules as say PHPMailer) and uses the FROM field as the sales rep. That is handled off in this case to Office365 to send emails. 

 

Actual Error:  Diagnostic-Code: smtp;550 5.7.60 SMTP; Client does not have permissions to send as this sender