Enabled multi factor auth on Office 365 Zoho will not send mail

Enabled multi factor auth on Office 365 Zoho will not send mail

I have tried to follow instructions to work with multi factor authentication activation on my company Microsoft emai account.

When trying to send an email I get the following error message:

535 5.7.3 Authentication unsuccessful [MWHPR2001CA0018.namprd20.prod.outlook.com]

How may I fix this?