Answered phonecall but caller didn't respond & hung up after a long pause of silence

Caller: I don’t know

Phoned twice within a matter of minutes. First time hung up after a couple of seconds and second time just silence for around 15 seconds before I terminated the call

Caller: ‘Andrew Wilson’ pretending to be Telstra

An Indian accent with very bad background noise. Do their best to convince they’re from Telstra… Calling regarding your internet service, wanted to speak to the owner of the account.

Don’t answer or just block… phishing and scammer number!

They never left a message.

Live in eastern Australia - called by a West Australian number - suspect. All out of area numbers to our landline are blocked. Had a call from 08 51146750 a couple of days ago - this number is associated to that number. They have tried a new number to try and defeat this number being blocked - Indian wankers with Telstra NBN scam.
When called back, mobile phone warns of being suspected spam and number is not connected. Also have tried calling using 08 5114 6741

Keeps calling but doesn't leave a message. Therefore I have blocked it.