Custom Domain: can’t recieve emails

Hi,

I recently created a custom domain, lets say example.com

I set it as Active, set the MX and TXT (spf trust) and create a few accounts, ex.: *** Email address is removed for privacy ***

I set to use Outlook.com as email provider.

I login to one of the accounts and test to send an email and the emails arrives.

Then from my personal account on Outlook.com try to send an email to the account on the custom domain but it never arrives.

Then i tried sent an email From Gmail to *** Email address is removed for privacy *** and never arrives.

Then i tried sent an email From *** Email address is removed for privacy *** to *** Email address is removed for privacy *** and never arrives.

What can be happening?

Best regards.