People are receiving phone calls that say they are from Telstra claiming you have been hacked , we have seen unusual activity on your account etc.
They will then talk you through installing remote desktop software (ammyy.com) and say you will need to pay for the cleanup or Telstra will disconnect you for 2 weeks.
This is a scam , just hang up and do not let anyone install remote software on your computer unless you are 100% confident that you know who they are.