If your smartphone is under warranty then go to the nearest service center they will help you but you need to show recording of your device when it goes stuck. They will troubleshoot all the software.
Sometime it's happen with a single device out of hundreds. If you still facing same issue after troubleshooting then you can ask for exchange your phone with other device. It will be an option of upgrade or same for your device
As per your query, you have already done the possible troubleshooting steps on your device but still facing issue. So, we would request you kindly visit the service centre and inspect your device with the technical team end, they will provide you with all the information in a better way after inspecting the device physically.
