Recieved a brand new iPhone 7 on 21/12. After two days the touch screen stopped working completely...not great over Christmas.On the 27th I went to a store in the City who advised that it was obviously a technical problem with the phone and it would be replaced with a new one after it was sent away for a few days, but that I needed to bring back the original box and accessories (not sure why if they could just swap the phone). Went to a store in the suburbs the next day with all the equiptment and my account details, where they said they couldn't locate my account details because it was ordered through a different system. They advised that once I had my account details they could send it off for me to be replaced or I could take it to an 'accredited store' where they could identify the issue was a technical fault and swap it over on the spot. When I asked where the nearest accredited store was I was told they didn't know 'but my manager thinks Eastland might be one'. The next day I spent 3 hours on the phone with Optus who hung up 4 times who kept telling me they can't locate my account so I mustn't be a customer. It wasn't until I suggested that if I wasn't a customer and they had been debiting my bank account for the last 4 years I should take it to the ombudsmum that they finally took my request to escalate my request seriously. I was then advised that my account had been moved to a new billing system, Jarvas, which is why nobody could help me. I was then moved to the Jarvas helpdesk where I waited another hour before again being hung up on. Called Eastland to see if they could just swap it and was told to speak to Apple directy - Apple, of course, said it wasn't their issue. So right now I am being debited $70 a month for a phone that doesn't work by somebody who doesn't recognise me as a customer. The only option I have is to go to the ombudsman to get this resolved. It is absolutely disgraceful. My requests to have this escalated to a second level support team were constantly ignored.
Sorry to hear of the issues with your phone! All devices is covered by a 24 month manufacturer's warranty, so Apple should be able to assess the device in accordance with your warranty here → Apple Products and Australian Consumer Law. Optus can provide a proof of purchase if necessary, but Apple can tell when the phone was registered so it's not usually required.
I personally go direct to the manufacturer as they often have service centres that can assess/repair on site, but if this isn't an option for your area then Optus can still send the phone away.
The process should be the same whether you have a Jarvis or Legacy account, so I'm unsure why there have been such difficulties previously.
Feel free to private message me if you have any issues going into the store again and I can follow up with their management.