Centene interview questions

Initial call with recruiter, which went well. He sounded optimistic and positive and that he'd "work with me throughout the process." Literally the next day, I received an automated rejection email with zero feedback from the recruiter himself. Seriously?

Submitted online application and interviewed with manager in person. Wrote thank you letter. Was not offered the position. What else can I say to meet the 30 word minimum? Thank you for the opportunity.