How to return faulty new iPhone 6S plus ordered from Apple Store online?

The new iPhone 6 S plus ordered from Apple Store online was just delivered by DHL. The phone could not be turned on; could not be charged and not recognized by my desktop computer. The invoice was issued by Apple South Asia Pte Ltd in Singapore. I have to return the phone by 15Oct. Can I return the complete package to this Singapore office And ask for refund? I do not want a replacement.