Telkom De;ays in Replacing under 7days New iPhone

I bought a brand new iphone 7 on 12 June 2018 from the branch at the Menlyn shopping centre, and I set it up the following day 13 June 2018. When purchasing I was told that if the phone presents any problems within 7days of purchase I am well within my rights to get a brand new phone. I was traveling to Cape Town on Thursday 14 June 2018, and I noticed while still at the airport that the battery was not charging to 100%, was used up very quickly (this despite all app notifications being switched off, even at night with zero activity on the phone) and the battery heated up while on just WhatsApp (and no other apps running). I took back the phone to the Telkom store on Saturday 16 June 2018, and was told the phone had to be booked in. I was obviously unimpressed with the gross inconvenience, but decided to let them carry out their diagnosis. I am now using a very old phone with a cracked screen as the reason for purchasing a new phone was because I lost my phone. On 22 June I contacted Telkom to indicate my frustration with their slow pace in giving me a brand new phone as they'd promised. I was told that iphones do not have a "7day faulty new phone replacement" and that my phone was going to be fixed. I asked Telkom to at least lend me a phone as I was putting my life in danger by using a phone with a cracked screen. All I was offered were apologies that they could not help me, and that I had to continue using the phone with the cracked screen while paying for a brand new iphone. I indicated to the manager helping me that Telkom and I could just part ways amicably as this is still a new contract to which she said; "YOU WOULDN'T WANT TO DO THAT, TRUST ME". It is now 26 June 2018; Telkom, how much time do you really need to ascertain that a phone has a battery problem??? If there is someone who can help me exit this contract cleanly, please assist.