I received a call at work from a Renton WA number, and immediatly after got a spam text message. When I called the Renton number back, it was a voicemail saying “Welcome to the Do Not Call database. If you would like to be added to the database, enter your 10-digit phone number.”
Note, no “Federal,” no mention of a US governmental entity. So I assume that it was actually an opt-in database for phone spammers, based on a bit of Googling around as seen below. One commenter remarked that it’s probably “out of country” spammers using some kind of bundling service based in Washington state.