An immediate hang-up after picking up points to a classic ping call tactic, where scammers test if numbers are active for future spam blasts. These calls often originate from overseas, like this New Zealand line hitting Australian mobiles, to avoid easy tracing. No words exchanged means it's likely automated probing rather than a direct scam attempt. To protect yourself, consider blocking the number right away, enabling call screening on your phone, and reporting it to your carrier or authorities like the ACCC in Australia. Staying vigilant helps cut down on these nuisances—don't call back unknown numbers, as that confirms your line is live.
An NZ number dialed my Australian mobile on 8 Aug 2025 at 9:23 am AWST; after I answered, the caller hung up instantly