Problem with Zoom OTP and Office 365 users

Hello!
All our employees can't log in into their accounts. 
Nobody receiving emails from ***********.
All our users using office 365 based emails.
We have check and apply needed changes in spam filtering rule using this KB: https://support.zoom.com/hc/en/article?id=zm_kb&sysparm_article=KB0060106
But our problem still not solved