can't receive emails last 12 hours

can't receive emails last 12 hours

Dear Zoho support,

We created a mail using our website 
We are able to send mails, but couldn't receive emails.
Kindly check the delivery report below.
Thanks in advance!



This is the mail system at host h2.appletec.ru.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

                  The mail system

<>: host mx.zoho.com[165.254.168.50] said: 552 5.1.1
   <> Mailbox delivery failure policy error (in reply
   to RCPT TO command)

Reporting-MTA: dns; h2.appletec.ru
X-Postfix-Queue-ID: 30C084405477
X-Postfix-Sender: rfc822;
Arrival-Date: Fri, 13 Jan 2017 08:38:19 +0300 (MSK)

Final-Recipient: rfc822;
Action: failed
Status: 5.1.1
Remote-MTA: dns; mx.zoho.com
Diagnostic-Code: smtp; 552 5.1.1 <> Mailbox delivery
   failure policy error

Return-Path:
Received: by h2.appletec.ru (Postfix, from userid 1026)
id 30C084405477; Fri, 13 Jan 2017 08:38:19 +0300 (MSK)