Mail delivery failed: returning message to sender

[Mail Delivery System]

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

  jipjop377 na gmail.com
    SMTP error from remote mail server after RCPT TO:<jipjop377 na gmail.com>:
    host gmail-smtp-in.l.google.com [64.233.166.27]:
    550-5.2.1 The user you are trying to contact is receiving mail at a rate that
    550-5.2.1 prevents additional messages from being delivered. For more
    550-5.2.1 information, please visit
    550 5.2.1  https://support.google.com/mail/?p=ReceivingRatePerm r18si10774551wrm.285 - gsmtp
  rin.rinek na seznim.cz
    Unrouteable address