Out of box damage

I recently took out a new Telkom mobile cell phone contract for a Samsung galaxy Note 4 on Thursday, just before the Easter weekend. I only tried to insert my SD memory card in the phone on the Monday, but the card was not registering on the phone. It works in other phones. I went into my nearest Telkom store in canal walk next to Pick and Pay, who confirmed to take the phone to the technician at the other Telkom store in the mall which I did. The technician inserted his own memory card which also did not register. He advised I return the phone to be replaced. When I approached Telkom as I wanted the phone to be replaced as it was an out of box fault, they told me they have to send the phone away for repairs. I refused as I wanted the phone to be replaced but they insisted the phone must be repaired. When I wanted to cancel the contract as it was within 7 days I was told there is no cooling off period and I would have to pay the full amount of the phone. This is TOTALLY UNACCEPTABLE as I am now sitting without a phone for at least 7 days!!!