I have a Salesforce org. Email address in Org is firstname.lastname@example.org and domain is a company name hosted on gmail.
When I try to send email(Using apex or standard "Send email" button from objects) to any of the email address of same domain, salesforce shows that email is sent successfully but email is not recieved to recipients. If I send email to gmail hosted email address like email@example.com, it works fine. Emails are recived by recipients.
I have also tested the "Test Deliverability" process in salesforce, same happens here.
Then I chnage my email address from firstname.lastname@example.org tpo email@example.com. It is working fine now. All emails are recived by recipients.
How I use the firstname.lastname@example.org email address in salesforce org and send email successfully(email@example.com is valid email address)?
Is there any setting which I need to check or set?