Error while processing the request! Outgoing Authentication Failure for

Error while processing the request! Outgoing Authentication Failure for

Hi, we have configured the Use My SMTP server using Office 365, and it was working till yesterday as expected. 
From today morning are facing some issues with outgoing emails and when we tried to check the SMPT configuration "Error while processing the request! Outgoing Authentication Failure for email.com" error message was thrown.

We have checked the credentials and everything is working, but don't know what the change is here.