Hi again @dennisedson and thanks for the reply.
As it turned out through digging through the API docs. When submitting a post to the Forms API, the email field must validate to a real email address. I was testing submissions using test@test.com and originally example@example.com since this is what HubSpot has listed in the docs as example JSON data. It’s a bit contradictory, but that turned out to be the issue.
I appreciate your help, though.
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