I have both your email and ‭(775) 997-5318‬ as a mobile number in my contact list.  Apple does not tell me which one it used when i just enter your name in the To field.  Another stupid apple example.
I don't why it sent email rather than text.

I'm googling around to see if I can figure it out. 

discussions.apple.com says:"The intended recipients email system is using a Barracuda mail server.Your email address or email provider has been blocked by Barracuda’s email reputation database or by the administrators of the email system you’re trying to reach.The intended recipients email system is using a Barracuda mail server.Your email address or email provider has been blocked by Barracuda’s email reputation database or by the administrators of the email system you’re trying to reach."But doesn't say what to do about it.

Another comment at https://powerdmarc.com/how-to-fix-550-spf-check-failed/ says,
"The “550 SPF check failed” message is a common error prompt that may be triggered by the absence of an SPF record in the sender’s DNS, the presence of an invalid one, or, third-party spam filters. The key takeaway from this type of error is that it is usually the sender’s fault, and not so much the receiver’s, and can be resolved with just a few quick steps.
SPF is an acronym for Sender Policy Framework, a protocol that forms the foundational element of email authentication and sender identity verification.
When you send an email from your domain, the email receiving server checks the domain’s SPF record to verify whether the domain name in the email’s return-path address is listed there. If no match is found, the email fails SPF authentication. "