Outlook Integration - not seeing emails in Monday.com

I have configured Outlook integration for our CRM board, so all my users can send emails through Monday.com, but I’ve found that it links existing emails within their inbox, associated to the email address as in Monday.com.

I’m finding now that specific users email accounts aren’t bringing over messages from Outlook, despite being linked. I did test this with my own email account and it did connect to previously sent emails. But this isn’t happening for at least one other use.

Am I missing something?