Hello Experts.

I am facing some issues with sending email from DBCS using UTL_SMTP

My package is as below:

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create or replace PROCEDURE send_mail (p_to        IN VARCHAR2,
                                       p_from      IN VARCHAR2,
                                       p_message   IN VARCHAR2,
                                       p_smtp_host IN VARCHAR2,
                                       p_smtp_port IN NUMBER DEFAULT 25)
AS
  l_mail_conn   UTL_SMTP.connection;
BEGIN
  l_mail_conn := UTL_SMTP.open_connection(p_smtp_host, p_smtp_port);
  UTL_SMTP.helo(l_mail_conn, p_smtp_host);
  UTL_SMTP.mail(l_mail_conn, p_from);
  UTL_SMTP.rcpt(l_mail_conn, p_to);
  UTL_SMTP.data(l_mail_conn, p_message || UTL_TCP.crlf || UTL_TCP.crlf);
  UTL_SMTP.quit(l_mail_conn);
END;

----------

Procedure call:

BEGIN
    ncr_send_mail('arun.pasupathy@aaa.com', 
                  'noreply@pprcuat.localdomain', 
                  'Test Message from SMTP - UAT 4', 
                  'localhost');
END;

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SMTP and ACL is configured on the Database.

When I call this procedure, I get the email, but it is inconsistent.
If I make the same procedure call 10 times, for example, I get email 5-6 times.
The remaining 4 times I don't get any email.

This is causing issues for me in many UAT code packages as emails are not sent consistently.

Can you please advise what I need to check.
Doesn't seem to be a code issue to me as I do get emails a few times.

Thanks in advance for your time.

Thanks,
Arun