Consumer's remorse

I recently made a purchase for a battery which was advertised on their website. The price was astonishingly low so I jumped to the oppotunity and made the purchase. But to my dismay I received an email stating that the product that I have purchased was out of stock and that I must reverse the payment. I responded to the email and asked when will the stock be available, but I did not receive a response from them. I tried again to reach out to them, to inform them that I cannot reverse the payment and besides it was going to cost me to do so, but to no avail. It is like they are ignoring my emails for some or other reason. I then sent an email requesting that they do an immediately refund, but that email to, was not responded to. I feel the next step is to approach the consumer council and demand that the product I purchased as per adverti*****t be honoured and delivered as per contract/purchase sales agreement.