Hi @mamood,
When reporting an issue is good to explain in detail what the problem is, show the logs with the errors, etc. Saying hi also helps 
Let’s check it.
You are sending a mail from mail.evexl.com to a gmail account and it is not delivered because the system thinks it is SPAM:
1.- Maybe you are sending spam or a mail that looks pretty close to spam.
2.- The mail server saying that your message is spam is not gmail but mta-us-002.bitrix24.com so you are not sending the mail directly from your mail server to gmail, you are using another mail server or you are using that mail server as a smtp relay.
3.- Your domain doesn’t have the right spf/dkim for mail selector records (at least not the ones used by Hestia):
It uses secureserver.net instead of your mail domain as it is the default in Hestia
$ dig evexl.com txt +short
"v=spf1 include:secureserver.net -all"
It doesn’t include the dkim record for mail selector:
$ dig mail._domainkey.evexl.com txt +short
4.- Your mail server identifies itself as sxb1plzcpnl489913.prod.sxb1.secureserver.net:
$ telnet mail.evexl.com 25
Trying 92.205.14.6...
Connected to mail.evexl.com.
Escape character is '^]'.
220-sxb1plzcpnl489913.prod.sxb1.secureserver.net ESMTP Exim 4.96.2 #2 Thu, 28 Mar 2024 07:13:09 -0700
220-We do not authorize the use of this system to transport unsolicited,
220 and/or bulk e-mail.
The server resolves to the ip 92.205.14.6 but the ip resolves to another server name 6.14.205.92.host.secureserver.net:
$ dig sxb1plzcpnl489913.prod.sxb1.secureserver.net +short
92.205.14.6
$ dig -x 92.205.14.6 +short
6.14.205.92.host.secureserver.net.
5.- You are not using Hestia. That server uses cPanel.
Hello, yes, you are right. I should explain the problem better, but I do not have enough experience to test the logs. Can you guide me to the steps that I will take?
You need to set up an external server to deliver emails for Bitrix24. Bitrix24 does not disclose their smtp server ip list so you cannot configure your DNS to authorize those…
Just use a different mail service for bitrix.