If your iPhone is already dead, we will first attempt to repair it while ensuring there is no data loss. But in case, it is stuck at a point where it is not possible to proceed without formatting or resetting the phone, we will call you and check if you have a taken an iCloud or iTunes backup. If you do not have a backup, we can return the device without resetting and you can try some data recovery solution. Once you have the data backup, we can continue with the repair.