Hope you're all well! Firstly, apologies - I'm certain this is a very very simple thing to resolve, but I just don't have the know-how! 

I receive the following email when I try to send a test to my new zoho address:

Delivery to the following recipient failed permanently:

      englishlessons@thenativeprofessor.com

Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the server for the recipient domain  thenativeprofessor.com  by mx01.easyname.eu . [146.255.61.215].

The error that the other server returned was:
550 relay not permitted, you need to authenticate


----- Original message -----

DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d= gmail.com ; s=20120113;
        h=mime-version:date:message- id:subject:from:to:content- type;
        bh=5ufAF2sS7hw3k2DflOscY/ GIuFAk06zK/xrekuddRHM=;
        b=Dr+Q6j+ 4sl2GtDDyud0nh1Ah152r6SxJ7Psd1 DnkOqE2mhFZgRTzmsxCBU8FETrlK4
         idUESKpySJpdoHkTGdQ2nH5u55m6s7 +g43b3fWF3rHI5BJ2wWaqqAv8ne/ poH/a6OQKt
         E6W/08bv3wmxWXb2Xw9LgPQbE59/ SgIkM+ Nq43lTdgG0FFyLVumcvsq5ciO7CvMe 58ME
         rFKf3IIrah/ S5XwREjrEFh3M0OYxXKLgsu97EPH6O qF8WrZ08pu9TbVPNvZdWWH6IL8X
         cGjLbnW2GhR5YSCtMgHPxPyZSTsc+ Vekr9qLROtuIuL/ Yvk6IPtr3QCendQspW8Oeqd7
         68OQ==
MIME-Version: 1.0
X-Received: by 10.107.4.213 with SMTP id 204mr22189146ioe.195. 1449331784444;
 Sat, 05 Dec 2015 08:09:44 -0800 (PST)
Received: by 10.36.137.136 with HTTP; Sat, 5 Dec 2015 08:09:44 -0800 (PST)
Date: Sat, 5 Dec 2015 16:09:44 +0000
Message-ID: < CADsSQxADkvuOxmdNSpbsFaREhiAzuLFmMqfnNyAMDXF3sfSCmw@mail.gmail.com >
Subject: testing 123
From: The Native Professor < thenativeprofessor@gmail.com >
To:  englishlessons@thenativeprofessor.com
Content-Type: multipart/alternative; boundary= 001a113ee6702c8487052628da80

testing 123

Could someone help me to resolve it? I really appreciate it!!