I called back number (03) 5357 2408 rang once then gets disconnected automatically.

Caller: Call Centre?

HANGS UP.

It must be a scam. When you return their call the message says "The number you have called is not connected"

This number keeps calling. Never leaves a message. If I try to call back, I keep getting a message saying the number is disconnected. I wish they would stop wasting my time.

Telemarketers

Just got one too. Origin stated as Navarre, Victoria . Guessing Spam

Two missed calls today. Call back and get Optus message the mobile number has been disconnected ... it’s not a mobile and I called back only a minute after the call.

This number calls multiple times.

Sometimes noone speaks, sometimes I get a hello, then when I ask who it is they hang up.

From a quick google it looks like a call back scam, where they hop you'll call back and the number is likely a premium call number.

Caller: 53572408

Called back, number disconnected.
Hit n run marketing cowards.

Call and hang up

Caller: Sleazeball

Hung up as soon as I answered. They probably want u to ring back so they can charge a timed call rate. I just blocked them.

hung up when I answered