One of my clients e mails are being rejected / Bounced back from my e mail address? can someone tell me why?

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to <roger@freelancecreative.biz>
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Remote host said: 550 <danavt@uaa.co.nz> sender rejected


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From: Dana Van Tiel <danavt@uaa.co.nz>
To: "'roger@freelancecreative.biz'" <roger@freelancecreative.biz>
Subject: FW: failure notice
Thread-Topic: failure notice
Thread-Index: AQHS+epWHj9vHksIpECScgxihgsoj6JN9c2g
Date: Tue, 11 Jul 2017 03:22:51 +0000
Message-ID: <7ee7d04f8a9d4e62a2ed8c6946994dbb@uaa.co.nz>
References: <44f272a5-bd16-4d5a-b515-122a275844f5@UAA-EX01.uaa.local>
In-Reply-To: <44f272a5-bd16-4d5a-b515-122a275844f5@UAA-EX01.uaa.local>
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