Anyone know why I get this error when I try to send an e-mail to them?

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Delivery to the following recipient failed permanently: ludvig.lindstrom@ globalhappiness.com

Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the recipient domain. We recommend contacting the other email provider for further information about the cause of this error. The error that the other server returned was: 550 550 5.1.1 <ludvig.lindstrom@ globalhappiness.com>: Recipient address rejected: User unknown in virtual alias table (state 14).
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Sorry, we were unable to deliver your message to the following address.

<ludvig.lindstrom@globalhappiness.com>:
Remote host said: 550 5.1.1 <ludvig.lindstrom@globalhappiness.com>: Recipient address rejected: User unknown in virtual alias table [RCPT_TO]
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The error persists whether I contact Ludvig or the e-mail advertised in their website, www.globalhappiness.com

I doubt it's the cause since it looks ok in the lower paragraph, but the first email address in your post has an errant space after the @. Might be worth correcting and retrying.