Can send but cannot recive emails on my cyberpanel webmail


I followed this guide

to start sending emails.

and I can send emails from the cyberpanel Webmail

but can’t receive any email from outside my domain.

I mean I can send from
test@mydomain to email@gmail

and can send from
test@mydomain to test2@mydomain

but cannot send from
email@gmail com to test@mydomain com

what should I do to start receiving emails ?

My project is developed with Django 3.2
CyberPanel Version:2.3
DigitalOcean - Ubuntu 20.04 (LTS) x64

can you please show me the checktls score?