Return of a toy to Smyths Toy store

Hi,

I bought a vtech toot toot parking station from a smyths toystore for my son as Christmas gift. This was instore purchase. My son saw the product after opening it, he didnt like it. So we decided to return it. The product was not used, it was in original packaging with receipt. However, the package was opened once (to see the product). We went to store and the store manager asked why do you want to return. We said we dont like it. He said, its your problem and I cant take it back. Its as per our return policy. Their policy does say item must be unopened.

Can you please advise me where do I stand? I tried calling their head office and they said they can not overturn store manager's decision.

Thanks