Poor service, poor quality Samsung S22

Hi there I recently upgraded my contract and got a phone for my wife. She has noticed that she hasn't been able to open the camera on the phone for the past 2 days and keeps getting an error saying "Warning Camera Failed" it also has faint blocks showing over the whole screen. I have taken it to MTN Longbeach Mall who said that it's definitely something wrong with the phone and covered under the Warranty, but because I ordered online they were unable to assist. I took the phone back in today to the Canal Walk MTN and was told to call your customer care line where I spoke to a lady who told me the device couldn't be replaced and the whole contract had to be canceled and now my wife is sitting without a phone (which she needs for work). I was told that it could take up to 14 days to cancel the contract. I need to take out a new contract in store for my wife urgently on the number so can this please be canceled immediately in order for me to open a new contract and get her a new phone.