Office 365 Unable to receive from external domains -- 2

Job ID: 33521260

Budget: £18 – £36 GBP

I am unable to receive emails from external domain to any of my office 365 users

I can send to external domain but replies do not come through]

I have no forwarders setup and I require senders to be authenticated is unchecked
Related categories: System Admin DNS Email Handling Office 365