Caller: Someone claiming to be a NBN representative calling in response to an email I sent.

I replied I didn't send an email concerning internet speed as I don't have a landline internet connection. I said "You sound like a scammer." He got very upset called me an idiot and hung up. I don't have a landline internet connection and I didn't send any emails. The fact that he got upset and called me an idiot would suggest that either NBN phone training protocols are inadequate or he was a scammer.