Can anyone tell me if I am being scammed?

[a chesters]

Here on Oz, we regularly get phone calls from the taxation office, supposedly, about a refund.

A friend recently got one, and annoyed the hell out of the scammer by bursting out laughing. He knew that he was going to have to pay extra tax when they went through the system, and was not going to get a refund

[Kaybron]

I have recently had 168 emails with a receipt from my power supplier thanking me for my $22 payment.  I phoned the power supplier after the sixth one and said that I had not made any payments.  He put me on hold and went off to check, then came back and said that someone was trying to put over $7,000 into my account and had set up for automatic payments of $22.  The person had used our account number.  There was a name on the receipt (not ours).  The person who I spoke to said that they had never seen anything like this and would have to investigate further and they would get in touch with the person on the receipt and get them to stop the payments.  Over 48 hours I was regularly receiving email receipts and approx. $3,700 had been credited to my account.  Have not received any emails from an unknown person asking for my bank details and to pay back the money which I thought this would be the next thing to happen.