Based on the provided information, it seems that the caller with the number +61280167790 is likely a scammer or telemarketer trying to contact individuals for unknown purposes. The fact that the caller claims to be from Sydney, but the recipient doesn't know anyone from there, raises suspicion. Additionally, the recipient recently acquired the phone, which might suggest that the caller obtained the number from a stolen or recycled phone list. The recipient's reaction to the call, calling the caller a "dummy", implies that the call was likely unwanted and potentially harassing.
I have no idea who this person is, they claim to be from Sydney, and I just got this phone from some guy in a pub carpark
I have blocked this number.