If your email was migrated over the past few months and you have just stopped receiving emails, it is likely due to your DNS records still pointing to the old platform.
You need to change your MX, CNAME, and TXT records as follows on each email domain you have for mail delivery and Outlook clients to function properly:
MX (only one as the host is load balanced):
v=spf1 include:spf.serverdata.net -all
If you do not know who your DNS provider is:
The results will show you who hosts your DNS.
This reference table are the most common:
|Domain on the Name Server||Company it belongs to|
|domaincontrol.com||Godaddy - Godaddy.com|
|worldnic.com||Network Solutions - networksolutions.com|
|cloudflare.com||Cloudflare - cloudflare.com|
|awsdns||Amazon Web Servers|