Hi @CourtneyPowell .
If you have a "Person" type column in SharePoint, when you're trying to create/update the field then you'll have to pass the claims. Which means if you have a field called "Assigned to" it will ask you to fill "Assigned to Claims".
The format for claims is "i:0#.f|membership|email@domain.com".
For example I have a Person field called "Employee", which should be the responder's email, then I can pass the claims in this format,

So you just need to append "i:0#.f|membership|" before the email.
Hope this helps 🙂
Kind Regards,
Shaik Sha
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