This was a missed call which showed as coming from Australia (no further information). They left no message and when I called the number back (a couple of times), their phone switched immediately to an engaged signal.This would indicate that the phone was in constant use and is most likely being used for scam calls (maybe a hijacked number). It remains to be seen whether they try calling back.

Offered discount electricity when I mentioned I don’t pay electricity they hung up abruptly