I blocked this number yesterday - then got a call today with the number reformatted to 061425498419 (ie 61 0425 498 419). I didn't say hello when I answered. It was really bizarre... a few beeps like a fax however also pauses. My phone screen came up showing 2 calls - a missed called from "No Caller ID" at 12:09pm and the "061425498419" as being the one I answered also at 12:09pm. Have blocked the 2nd one now.

Caller: I don't know

Long pause then some accented call centre w@nker calling me by a previous name (clearly doesn't know me!) going on with a spiel even when I was trying to pull them up telling them I don't care and they clearly have no idea who they are talking to. Block Caller!