Could you expand on what you mean by not working?

To set up a wildcard CNAME, the DNS panel should look like:

DNS can take some time to propagate fully, and if the domain was previously pointing somewhere else you may need to clear your local cache.

Heyy Thanks for your answer...Got the issue and fixed it...Now, ia was trying to configure mail server using

https://www.digitalocean.com/community/tutorials/how-to-configure-a-mail-server-using-postfix-dovecot-mysql-and-spamassasin

I followed all steps, but looks like there is some issue. When i telnet on port 993, it gives me error