Device faulty after 8 months

So currently holding on the phone now as we speak for 17min15sec while a woman checks "what parts are being ordered for my 8month old Huawei P20"so I ask you.... how can a phone need repairs at 8 months old? So now my phone has been opened and tampered with I have literally 4 months left of "warranty" and its broken already and burnt my son on his hand and now I must still pay the full term 24month contract for a phone that's already broken and tampered with..... I cannot understand that if this is a phone error especially a phone heating up like this that I be given a new phone. Im highly disgusted with the treatment I am getting with regards to my phone. I don't want a phone that's been tampered with and opened that's not what I am paying monthly for. IF this is a issue and its burnt someone then destroy the device and issue another one as this is dangerous. ***