PHP Mail error

I am sending PHP mail but I am getting an error from the server and the emails are being Quarantined.

Here is what I have:

<?php
$headers = 'MIME-Version: 1.0' . "\r\n";
    $headers .= 'Content-Type: text/html; charset=UTF-8' . "\r\n";
		
	$headers .= 'To: '.$to."\r\n";
	$headers .= 'From: '.$from."\r\n".' Return-Path: '.$from."\r\n";
	
	@mail($to, $subject, $message, $headers);

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These are two of the errors.  Please look at the return path.
Console_2017-03-08_15-15-17.png
Console_2017-03-08_15-21-41.png