Likely scam or phishing, rang back, "your call cannot be connected"

called back says call could not be connected

Caller: Recorded message

This call showed as coming from Sydenham, Victoria. It also bore a warning message which said "Warning: Suspicious Calling Pattern". I answered the call, only to hear silence for several seconds, then a recorded woman's voice which said "goodbye" and the call was terminated from the other end. I strongly suspect it was an attempted scam, albeit a rather strange one!