Called back, hold music playing

I decided to answer. It was obviously an overseas call centre from the background noise, a woman I could barely understand. I hung up. Blocked.

Called with a scam, autoblocked and moved on.

Didn’t leave a message = scam

They knew my name but it was for sure some spam call center. They hung up when I grilled them.

Some sort of boiler room scam trying to sell me a financial scam product about extra income. Barely understandable accent on a low quality line. Not sure who falls for this nonsense.

Phone disconnected when I called back

Received a call. They didn't leave a message.

No message left when I did not pick up, looks like a scam from the comments above.

Received a call. They didn't leave a message. I called back and received the standard message of "the number you have dialled is not in service, please check the number and try again".

Caller: (03) 9862 3422

As above