Some Indian guy talking about "federal law". I hung up on him.

Caller: Scam

It's a Solar rebate crap, scam don't answer. Indian call center

Caller: Didn't answer

When I call back, I hear a familiar "Thank you for calling customer service" recording, of course, without identifying who they are. Whether scam or spam or even real company, that's always dodgy. (Familiar because it's the same voice and recording I hear for many such missed calls which I call back)

Call came up as suspected spam, I didn't answer call and no message was left.

Caller: 0489 905 840

Answered and instantly hanged up. Called back and went straight to 'this phone number is not available'

Did not recognize number, when answered there was silence a then they just hung up. Blocked.