Shopify Email Order Notications Rejected - "Undelivered Mail Returned to Sender"

Shopify Email Order Notications Rejected - "Undelivered Mail Returned to Sender"

Please help! I am wanting to use Zoho as the host for my Shopify emails. I need notification emails for incoming orders to be sent to my email I have registered - I have followed all steps posted on Shopify and Zoho. Here's the reject message that I receive in Zoho - can anyone assist?

This is the mail system at host smtp.shopify.com. 

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 

<Info@littlecomfortcare.com>: host mx.zoho.com[204.141.42.121] said: 554 5.2.3 
MailPolicy violation Error delivering to mailboxes (in reply to end of DATA 
command) 
Reporting-MTA: dns; smtp.shopify.com 
X-Postfix-Queue-ID: 7BAC313DB69 
X-Postfix-Sender: rfc822; Info@littlecomfortcare.com 
Arrival-Date: Thu, 23 May 2019 16:34:43 +0000 (UTC) 

Final-Recipient: rfc822; Info@littlecomfortcare.com 
Original-Recipient: rfc822;Info@littlecomfortcare.com 
Action: failed 
Status: 5.2.3 
Remote-MTA: dns; mx.zoho.com 
Diagnostic-Code: smtp; 554 5.2.3 MailPolicy violation Error delivering to 
mailboxes 

Return-Path: <Info@littlecomfortcare.com>
X-Path-Id: 7BAC313DB69
DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=shopify.com; s=mail; 
    t=1558629283; bh=hdoqSFv874XKrqaho/+ScpHYoEnDfJ9Ufxw+T28X4cU=; 
    h=Date:From:To:Message-ID:Subject; 
    b=LG3KdyEfMeWdnmGyg/jS6926oXVvn0+NuH8oNRFvdf/KbY43J/USZGTEmJ4XInj+t 
     9Du40kznnrVjMx0JxzflvLEHP/d99Vxk9dc2TuCmbwM5He7ytLa/7iEgj4ZL+ltnkj 
     13mQMkzBaWKr8+tlK4Fhj14ImZVzBFg2HmMKmMk4=
X-Path-Id: 6E18B140005
Date: Thu, 23 May 2019 16:34:43 +0000
From: Little Comfort Care <Info@littlecomfortcare.com>
To: Info@littlecomfortcare.com
Message-ID: <5ce6cba35c633_393fce33cd460065557@shopify.com>
Subject: [Little Comfort Care] Order #1009 placed by Jonathan Reck
Mime-Version: 1.0
Content-Type: multipart/alternative; 
boundary="--==_mimepart_5ce6cba35c274_393fce33cd4600654ca"; 
charset=UTF-8
Content-Transfer-Encoding: 7bit