Email getting bounced as spam

[thegraph]

Had three different emails get bounced  - two of them I was replaying to an email I received. I sent an email to hostdash as they helped us set up our account - that got bounced.
Any ideas? This used to happen with our old service provider FutureQuest, but hasn't happened with Webmail.

Thank you for any ideas.

Here is the message I received:
 sales@hostdash.com
   host relay.mailbaby.net [67.211.215.74]
   SMTP error from remote mail server after end of data:
   550 This message was classified as rSPAM and may not be delivered https://mail.outboundspamprotection.com/mailinfo?id=18ab4a591d30002aba&user=mb20610
Reporting-MTA: dns; us1.providedns.com

Action: failed
Final-Recipient: rfc822;sales@hostdash.com
Status: 5.0.0
Remote-MTA: dns; relay.mailbaby.net
Diagnostic-Code: smtp; 550 This message was classified as rSPAM and may not be delivered https://mail.outboundspamprotection.com/mailinfo?id=18ab4a591d30002aba&user=mb20610