All they did was left an automated voice recording to call them back at 530-770-2675.

When you call that number back with an unlisted phone number, the call fails and gets dropped.

Sounds like a new telemarketing scam trying to fish people by leaving you the automated voicemail recording sound important so when people call back, they can verify live phone numbers.

Scam Scam Scam

A legit business would answer any calls from listed or unlisted phone numbers and would provide their business name when they answer.