Frustrated !!! Incredible connection

So I recently purchased a Xiaomi redmi note 9s from the Glen shopping centre in Johannesburg.The unit is only about four or five months old and under warranty... Last week while using the above mentioned device, it heated up severely.i immediately removed the leather pouch to allow for my device to cool down.To my surprise the glass back had cracked as a result of the overheating. This unit was never dropped and always protected by a screen guard and the original leather pouch. On Sunday the 24th January 2021 I had taken a drive to the Glen shopping centre to seek assistance at the incredible connection store.The technician Sibusiso was friendly... however his and his managers knowledge on the product was extremely limited. The manager was insistent that that it was physical damage however the device clearly indicates that the unit never fell down. They both could not assist me with contact details for the agents in South Africa.They also both had zero Idea as to where the service center is located. Also when purchasing the unit from them, the staff were extremely friendly and helpful but when it came to after sales service,I just can't say the same... Very disappointing Indeed.After purchasing my device last year August I was so chuffed with the service so I encouraged my wife to buy her New device from the same store...My frustration levels have sky rocketed... I am utterly disappointed.... Also disappointed at the Xiaomi and redmi South Africa for not maybe educating the staff of Incredible connection as to how they should address issues with regards to the above mentioned product. The store manager actually said that I would be charged a fee of Three hundred and fifty Rands for the collection of my device from their store....can you believe the nerve! Incredibly Poor Connection