A DMARC policy allows a sender to indicate that their emails are protected by SPF and/or DKIM, and give instruction if neither of those authentication methods passes. Please be sure you have a DKIM and SPF set before using DMARC.
You do not have a DMARC record, please add a TXT record to your domain _dmarc.dorax-investments.com with the following value:

v=DMARC1; p=none
Verification details:

mail-tester.com; dkim=pass (1024-bit key; unprotected) header.d=dorax-investments.com header.i=@dorax-investments.com header.b=X3bm8ssx; dkim-atps=neutral
mail-tester.com; dmarc=none header.from=dorax-investments.com
mail-tester.com; dkim=pass (1024-bit key; unprotected) header.d=dorax-investments.com header.i=@dorax-investments.com header.b=X3bm8ssx; dkim-atps=neutral
From Domain: dorax-investments.com
DKIM Domain: dorax-investments.com