This is a regional NSW number - called my mobile in another state. Called it back later and it just clicked off mechanically, immediately without the dialling sound. Get this so often, it's a robot caller.

Caller: Supposably immigration

(02) 7238 7478, I didn’t speak just answered the phone and auto message said it was immigration, man that came on the phone sounded Chinese. It beeped before he spoke, muted him & he hung up