A scam number has been charged to Telstra mobile customers following a breach in their system.

The fee will come up as a "Third Party Purchase" on your Telstra Mobile bill.

Telstra support staff said it is a scam following a breach in Telstra's networks where they gain access to your mobile number and make a series of calls to premium services.

The billing amount is $39.95.

The would be "hackers" make a series of 6 calls in one minute that returned the above amount.

Anyone who has these charges, call Telstra on 13 22 00 and insist to talk to a supervisor.

 "Dialogue Communications" can be contacted on 1300738639 and they will tell you ring Ordanduu on 1300886232 and ask for a refund, they will offer you a refund by cheque. The scam works when you click on www.quiz2winmycar on your PC and you fill in a survey.

Unfortunately someone I know filled out the survey and the next Telstra bill had this $39.95 charge.