ERROR_CODE :550, ERROR_CODE :DKIM pubkey_unavailable

ERROR_CODE :550, ERROR_CODE :DKIM pubkey_unavailable

Hello,

Can't deliver emails to certain domains. Error i receive is: 

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. 

xxx@qafqazriversidehotel.com, ERROR_CODE :550, ERROR_CODE :DKIM: encountered the following problem validating travellerto.com: 
            pubkey_unavailable 

xxx@qafqazhotels.com, ERROR_CODE :550, ERROR_CODE :DKIM: encountered the following problem validating travellerto.com: 
            pubkey_unavailable 



Received:from mail.zoho.com by mx.zohomail.com 
    with SMTP id 1506854481252737.4562691783816; Sun, 1 Oct 2017 03:41:21 -0700 (PDT) 
Message-ID:<15ed786ad50.ed0ed40e561298.4075676344135060725@travellerto.com
Date:Sun, 01 Oct 2017 03:41:21 -0700 
From:reservation travellerto <reservation@travellerto.com
User-Agent:Zoho Mail 
To:"xxx" <xxx@gmail.com>, 
    "xxx" <xxx@qafqazriversidehotel.com>, 
    "reservation" <reservation@qafqazhotels.com
Subject:reservation for Mejahed Naser Alhajeri 
Content-Type:multipart/alternative; 
    boundary="----=_Part_1800775_2135996318.1506854481249"

I updated DKIM records domain control panel. Could you please check and help with this issue?

Thanks!