Scam number they want you to call back and it costs you heaps

Some dodgy Indians called claiming to be from NAB Masterard. They reckoned there was a suspicious transaction on my card from Perth. Then wanted me to log in, also wanted to know if I had the NAB app on my phone. I then disconnected.

This number 0435 838 845) has called me 8x times in 5 days. only missed calls, no VM left. I did answered a couple of times and they say i have won a prize, based on a entry made from from an old email address that I no longer use.
I told them I have no entered into any prize nor do i use that email address any more. they then suggested i was scammed and someone must have entered on my behalf.
Very odd! Not sure of the company name or any details other than that.

I told them to remove my number and stop calling but they still continue to try and call me. So frustrating!

Scam - called back and was asked to remain on hold for their next available agent.

I called back the number 0435 838 845 and reached vm that said I reached Premium