I have a domain (ex:- mydomain.com). I am using sendgrid mail service to send and receive mails. When I send any mail using sendgrid V3 API from address [email protected] it is working fine. But I when try to use sub-domain [email protected] sendgrid throwing 403 error (domain is not authenticated). Looks like it is accepting only root domain with out any subdomains. I would like to send emails from different custom subdomains.(like freshdesk and zendesk which allocates a different sub-domain for every user). Is there any way that I can overcome this probelm ?
Any little help would really be appreciated.