Hello @CaseyK28 ,
You can find a drilldown of bounce types and their reasons on our main article on managing them, as well as in the actual bounce report for your email. Most likely, your ISP, email program, or some other system that filters your emails is treating the fact that a 3rd party service was sending an email to your address, claiming to be from your address. In that regard, we'd advise looking into email authentication, particularly self-authentication if you have your own domain.
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